PDA

View Full Version : German a/c nose cannon accuracy



Holtzauge
02-17-2006, 02:39 PM
In this sim, the accuracy of German a/c nose cannons is off and should IMHO be corrected. Especially the Mk108 which lobs shells all over the place.

In both references below there are sections detailing how to calibrate the guns.

In ref 2, Schusswaffenanlage, page 40, section 13, the following spread is allowed for the gun installation: At 100m Mk108: All shells should hit within an area of height 35 cm and width 30 cm.

Compare this to the Mg131 installation in the G6/U4 the accuarcy requirement is height 100 cm and width 100 cm.

So IRL the Mk108 spread is significantly lower than the Mg131 spread!

This data is not reflected in the sim behaviour in which 30 mm shells are lobbed all over the place.

Oleg, please fix it!

References:

1) D. (Luft) T.2109 G-6/U4 teil 8A heft 1 Ausgabe April 1944. (This is part 8A of the Me 109 G6 a/c manual which covers the gun installation of the U4 variant which was equipped with a Mk 108 instead of a 20 mm in the nose)

2) Ta152 H-0 und H-1 Vorlaufiges Flugzeug-Handbuch, Schusswaffenanlage, Dezember 1944

AustinPowers_
02-17-2006, 02:42 PM
hehe, man this thread is gonna rock tommorow. http://forums.ubi.com/images/smilies/clap.gif

Gibbage1
02-17-2006, 02:52 PM
Pop up some popcorn. This will be entertaining, be sure!

JG52Karaya-X
02-17-2006, 03:08 PM
Not if the usual trolls stay in bed - which I doubt http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif

VW-IceFire
02-17-2006, 03:15 PM
I think you need to do a search of all previous threads pertaining to this topic over the last 4 years http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Hurricane_320
02-17-2006, 03:17 PM
Let see. . .

<UL TYPE=SQUARE>

Popcorn - yes

Vodka - yes

Gun for self defence - yes

F-Secure Anti-Whiner - yes

Windows firemoderatorwall - yes

A quick key for IBTL - yes

Good, we'we got it all!

[/list]

Gibbage1
02-17-2006, 03:20 PM
Originally posted by JG52Karaya-X:
Not if the usual trolls stay in bed - which I doubt http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif

Im already here. http://forums.ubi.com/images/smilies/784.gif

Low_Flyer_MkVb
02-17-2006, 03:21 PM
Covering your six, Gib. http://forums.ubi.com/images/smilies/icon_twisted.gif

Gibbage1
02-17-2006, 03:47 PM
Well it looks like nobod is willing too take a crack at this. I will start off things.

#1. What aspect do you think contribute too the Mk-108's remarkable accuracy?

Was its low velocity? How about its short berral? Maybe its extreamly light round in comparison too its size? Maybe its the very light aircraft it was attached too?

All these factors DONT contribute too a low dispersion, but CONTRIBUTE too its rather high dispersion!

#2. Have you done ANY testing on this, or are you here just posting your un-informed and rather un-biest openion? Should we trust your word that the dispersion is in fact rather bad?

#3. What other proof do you have other then pilot openion? Im sure I can find a few pilot quotes to counter any you dig up about it being rather innaccurate, and they were just spraying what ammounted to a rappid fire grenade launcher in the area of a bomber formation in hopes something hits. How about German documents that list's the guns dispersion in mils?

MLudner
02-17-2006, 04:04 PM
Actually, Gibbage, are you sure that was a pilot report?

"In ref 2, Schusswaffenanlage, page 40, section 13"

"2) Ta152 H-0 und H-1 Vorlaufiges Flugzeug-Handbuch, Schusswaffenanlage, Dezember 1944"

Handbuch sounds like "Handbook" to me.

georgeo76
02-17-2006, 04:10 PM
Dispersion and accuracy are two different things.

the lighter MG rounds would disperse more because their inertia would be less and therefore forces acting upon them would have greater effect.

If the tests were similar in fire time; not in rounds fired, the more numerous MG rounds would be expected to have more variation.

If the testbed was a 109, and not the guns alone, the MG would have two point of origins, centimeters off the center of convergence. The MK108 would be at the center of that axis.

@ 100m all guns have very low dispersion.

This seems to already be factored in the game, as MG streams do disperse more than a Mk108 stream @ distance. However, the trajectory of the 30mm shells is much different(and worse).

Gibbage1
02-17-2006, 04:26 PM
Ya. 100M is not that far away. If your 100M frm an enemy bomber, your taking hits. The Mk-108 was fired at MUCH greater distances then that.

Also, has this joker done ANY testing within IL2 to see if his feelings have any base in reality? Maybe he should do the standard gun test and put a house 100M in front of him on the runway and fire at it. Takes 5 mins to do that test.

When we did testing on the .50's we tested at 300M, a more respectable distance, but that corrisponded with the documentation we had that listed its dispersion as 15 mils at that distance.

JG53Frankyboy
02-17-2006, 04:38 PM
install IL2 1.0 - there you will have your MK108 "sharpshooter" gun http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Gibbage1
02-17-2006, 04:50 PM
Originally posted by JG53Frankyboy:
install IL2 1.0 - there you will have your MK108 "sharpshooter" gun http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Or how about the Mk-103? Its got a much longer berral, greater charge, MUCH higher MV, and is a much heavier gun making it a more stable platform. All the ideal things for an accurate gun the Mk-103 DONT HAVE!

p1ngu666
02-17-2006, 04:57 PM
the dispersion of all guns is surprisingly high when i tested a week ago.

using test runway and chocks, we can test for dispersions very well http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Jumoschwanz
02-17-2006, 04:57 PM
The BRITISH tested a mk108 during WWII, and said it was not effective beyond 600 meters....

I will take that any day, as I don't use any guns anywhere close to that range.

Jumoschwanz

NonWonderDog
02-17-2006, 05:10 PM
You know, 35 cm at 100 m is still 12 MoA... and that's not even for a plane in flight. That's not exactly a precise firearm. http://forums.ubi.com/images/smilies/53.gif

I never noticed an absurd amount of dispersion in the MK-108 at 100m, either. That 35 cm mentioned is quite a lot, you know -- it's more than enough to make you miss a wing quite often, and most people fire from 200-300 m in the sim!


But just as a tolerance value, and not an actual test, it's not very useful for comparison. Just because the MG-131 had a greater installation tolerance (installed in pairs, off-axis!), doesn't necessarily mean that the weapon was less precise. It mainly says that the Mg-131 wasn't as critical a weapon, to me.

carguy_
02-17-2006, 05:20 PM
600m is a little far,don`t you think?Ingame MK108 loses any effectiveness above 350m.

Someone who doesn`t post here anymore posted tests in 2.04 IIRC that proved the lobbing.Suggestion was that setting convergence on nosegun indeed affects the lob effect which is higher the further conv.point is specified.So when conv is set to 100m(minimal) the lob effect will be next to none but the dropping of the fired shell will occur prematurely thus no long range shooting is recommended.


In FB the MK108 was a very bad weapon ballistic-wise.A very good thread was made to provide tests and data which undoubtetly proved the problem was there.After that when the patch got released it became an effectve gun.Whines pretty much came to an end.

Pilot accounts indeed state that during firing, the nose shaked violently.Pilots generally never used it in above 150m range.
Previous problem wiith MK108 was also heavily influenced by uber muzzle flash which proved to be one of the biggest shooting accuracy factors.The muzzle flash change was a revolution particulary for nose armed aircraft.


Actually it`s hard to believe the MK108 could be proven to be even more effective in real life.The tracer is clearly visible and effective shots up to 350 meters are possible.

However,if a good portion of data compared to intensive and honest testing was presented,this "issue" can be very interesting.I am sure the whole red lobby will try to take the thread down asap as we already see but they should be ignored IF the original poster provides a good quality/amount of data.

Kocur_
02-17-2006, 07:19 PM
Dispersion does not decreace with increaced lenght of barrel. Lenght of barrel serves muzzle velocity (OTOH: which increaced reduces dispersion secondarily, as projectile spends less time in atmosphere). Parameter of barrel which defines dispersion is its stiffness. Obviously the shorter the barrel is, the more stiff it is - assuming equal thickness of walls.
So short barrel of MK108 - dictated by principle of action, which was defined by demands of low weight of the gun - served dispersion well: +

The heavier the projectile - the less dispersion due to atmosphere influence:+

The differece in design to make MK108 disperse less than MG131 is fact, that in the barrel of the latter it was movable as the weapon was recoil operated, and fixed in MK108:+

MK108 was API blowback operated weapon, i.e. large part of recoil was 'consumed' by the bolt returnig to battery position - primer was ignited before the position was reached:+



Hopefully none of us will confuse (anymore) dispersion with accuracy understood as probability of hitting a target of certain dimensions at certain distance. The latter decreaces with increace of maximum ordinate at a distance, which increaces with decreace of MV and BC http://forums.ubi.com/images/smilies/winky.gif. And trajectory of MK108 projectiles surely was among the most arched among WW2 aerial weapons.

So dispersion of MK108 was low, but it was more difficult to hit a target than in flatter trajectory weapons, due to high trajectory, as pilot had to judge distance well to use proper elevation. OTOH at short distances it didnt make it 'totally inaccurate' as some might belive. It still was no mortar and the targets werent ants.

Btw: sectional density of .50 AP
0,36 g/mm^2

of 3cm Minengeschoss
0,46 g/mm^2




What aspect do you think contribute too the Mk-108's remarkable accuracy?
Was its low velocity? How about its short berral? Maybe its extreamly light round in comparison too its size? Maybe its the very light aircraft it was attached too?

All these factors DONT contribute too a low dispersion, but CONTRIBUTE too its rather high dispersion!

Gibbage1
02-17-2006, 07:25 PM
I still see no test's. Just a lot of assumptions.

I remember how many fricken test's and comparitive data I had too throw up on the forums before I got any backing.

Just comming from someone who had to fight to fix dispersion as a gun, so far the Mk-108 lobby team is doing a piss-poor job.

Grey_Mouser67
02-17-2006, 09:33 PM
Originally posted by Jumoschwanz:
The BRITISH tested a mk108 during WWII, and said it was not effective beyond 600 meters....

I will take that any day, as I don't use any guns anywhere close to that range.

Jumoschwanz

I had read somewhere...can't remember the source, that Luftwaffe pilots typically got less than 200 meters from bombers before opening fire.

In addition, maybe someone has some more definite data, the Mk108 was such a low velocity weapon that if it lost enough muzzle velocity, it would not detonate the explosive head....the range was longer in head on attacks and much less in tail to tail attacks....

Anyone ever wonder why a Me-262 has four of these cannons? Seems like two with much more ammo would make sense given the way the guns are modelled in this sim?

Personally, I believe the guns are verrry optimistic...but what the heck, I've never fired them...and yes 35cm at 100 meters is ALOT of dispersion...especially if the weapon is locked in place and firing one round at a time.

Aaron_GT
02-18-2006, 02:11 AM
Well it looks like nobod is willing too take a crack at this. I will start off things.

#1. What aspect do you think contribute too the Mk-108's remarkable accuracy?

Was its low velocity? How about its short berral? Maybe its extreamly light round in comparison too its size? Maybe its the very light aircraft it was attached too?

All these factors DONT contribute too a low dispersion, but CONTRIBUTE too its rather high dispersion!

Disperson comes from two sources - within the barrel, and after the round leaves the barrel. A low velocity round will be more affected by factors after leaving the barrel, and this will increase with travel time. It isn't necessarily the case within the barrel. The MK108 was designed to have a very stiff barrel, which is good for low dispersion, and it was kept short to reduce weight. Thus for short distances (e.g. 100m) the MK108 should be pretty accurate as atmospheric conditions (wind, etc) haven't really had a chance to affect its progress. At 300m it would be a different picture, but the quoted figures are for 100m. At 300m the travel times would also be such that hitting a fighter target in a dogfight would be difficult, but then many pilots liked to get in much closer than this. The long travel times and dispersion at 300m are a bit less of a problem for engaging bombers as they are bigger and in formation.

Aaron_GT
02-18-2006, 02:15 AM
Anyone ever wonder why a Me-262 has four of these cannons? Seems like two with much more ammo would make sense given the way the guns are modelled in this sim?

You get diminishing returns for increasing number of guns mounted in terms of chances of at least one hit, but there is quite a jump from 2 guns to 4 guns against a fighter sized target.

Plus Me 262 engagement speeds would be quite high so the time for firing would be much reduced. To down a bomber on average you still needed around 3 30mm hits, and with a very short pass 2 guns might not be enough to reliably deliver this with typical pilot skills. Given that jet engines were also pretty vulnerable you wouldn't want to expose yourself to multiple passes. And if the plane can carry 4 without degrading performance too much, why not?

Hurricane_320
02-18-2006, 02:20 AM
http://forums.ubi.com/images/smilies/sleepzzz.gif

Gibbage1
02-18-2006, 02:45 AM
There is an extreme lack of testing in this thread.

JG5_UnKle
02-18-2006, 02:54 AM
Originally posted by Gibbage1:
There is an extreme lack of testing in this thread.

Well volunteered http://forums.ubi.com/images/smilies/clap.gif

Gibbage1
02-18-2006, 03:32 AM
Originally posted by JG5_UnKle:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Gibbage1:
There is an extreme lack of testing in this thread.

Well volunteered http://forums.ubi.com/images/smilies/clap.gif </div></BLOCKQUOTE>

I faught my fight for the .50 cal. I hate the Mk-108's so its not my fricken job to make them any better or worse. But I am not going too sit around and let a bunch of blue players say "Mk-108 not uber enough" and "Ja ja! Oleg fix it!" without proof since I am sure as he11 they would do the same in kind and DO the same when any similar Allied post's.

Without oposition, everyone here would agree the Axis won and the 109 was the best fighter ever http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Holtzauge
02-18-2006, 05:27 AM
It is interesting to note that most of posts calling for a tests and proof are the ones most devoid of any facts but filled to the brim with biased unsubstantiated opinions.

My original post contained references to sources of calibrating guns on German a/c. The same sources also contain values of dispersion for wing mounted gun installation such as the mk151 and others.

All these sources say the same thing: The nose installation was the one with the lowest dispersion and best accuracy.

How does that tag with how the sim behaves?

Believe me I know that posting this will most probably not change anything but the shortcomings of this sim should be pointed out and it is always entertaining to note the reactions. http://forums.ubi.com/images/smilies/59.gif

During the many occasions that threads about this have come up I have seen no data or facts saying it was the way it is modeled in the sim.So what speaks against the referenced documents and supports that the Me 109 shook like a leaf when firing the Mk108?

Personally, I put more trust in wartime documents detailing allowable dispersions for different gun istallations than the unsubstantiated opinions made in some of the posts above.

Aaron_GT
02-18-2006, 09:02 AM
Stop bringing up facts, Holtzauge! You know that isn't the correct way to do things round here :-)

NonWonderDog
02-18-2006, 09:06 AM
Err, he's given the installation tolerances for both a primary weapon mounted on the nose and secondary weapons mounted in pairs off-axis.

Lo and behold, the primary weapon has a tighter tolerance.

These figures aren't directly related to actual dispersion. They give no information about normal dispersion of each gun. About the best that can be said is that the most inaccurate MK-108 was required to be more accurate than the most inaccurate MG-131. I'm not sure if that means anything useful.

I'm not sure if the maximum 34 MoA given for the MG-131 is even physically possible. I mean, that's smoothbore musket accuracy, or worse.

MLudner
02-18-2006, 09:08 AM
Originally posted by Gibbage1:
I still see no test's. Just a lot of assumptions.

I remember how many fricken test's and comparitive data I had too throw up on the forums before I got any backing.

Just comming from someone who had to fight to fix dispersion as a gun, so far the Mk-108 lobby team is doing a piss-poor job.

I believe, Gibbage, as I said above, that the original poster was going on Luftwaffe test data.

Why are you so assiduous about this discussion? (We still need a head-scratching smiley...)

karost
02-18-2006, 11:06 AM
mk 108 in BF-109G-10 , Ta-152 is ok
mk 108 in BF-109G6a/s is bad

mk108 quite good when shoot target below 120meter when shoot target with speed less then 400 km/h by add more deflection line about 25 - 35 meter from target's nose fight path.

over 150 meter shooting a fighter plane not work for me.

S!

Stafroty
02-18-2006, 01:25 PM
well, at least airrifle 4.5mm, is FAR more accurate, than is MK108 in game, its ammo weights some gram, and muzzle velocity is under 200m/sec..

also, so is full auto splatter gun, if its adjusted right. it shoots balls, like did musket rifles. no rifling like in MK108.. but of course...

again, useful range of AGL-1 Plamya is 800m on direct fire,. and 1600m indirect fire, and it had muzzle velocity of some 170m/sec, used full auto or single shot, on tripod, weighing total some 50 kg with magazine added. using almost the same ammo as is MK108.

why is the MK108 so poor, why does people WANT to "believe" it WAS so poor?

is there any BIAS behind this?

does it give too big advantage to others, so balancing is "needed"??? its like .50cals bullets are flying too far away compared to other guns in game, far over useful range in terms of KE if enemy plane is flying away, while, HE ammo doesnt lose its power as does KE based ammo..

Cobra-84
02-18-2006, 01:34 PM
Originally posted by karost:
mk 108 in BF-109G-10 , Ta-152 is ok
mk 108 in BF-109G6a/s is bad

How is that possible? Its the same exact gun with same data in game on all three planes. They seem the same to me.


Originally posted by MLudner:
Why are you so assiduous about this discussion?

No tracks, screenshots, or other in game tests, just an "I feel..." and some "data" with no link or anything. Is he is just supposed to say "go ahead, "fix" it" with no proof? If thats the way it should work, I'm going to start a thread about I demand P-47s be armed with 4 120mm cannons and AIM-9s, offer little to no proof and expect full agreement?

The Mk-108 accuracy is fine. if you can't get hits at 600m or more, its time to take a trip to the optometrist or shooting range.

karost
02-18-2006, 02:06 PM
Originally posted by Cobra-84:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by karost:
mk 108 in BF-109G-10 , Ta-152 is ok
mk 108 in BF-109G6a/s is bad

How is that possible? Its the same exact gun with same data in game on all three planes. They seem the same to me.

</div></BLOCKQUOTE>

Cobra-84: my point is about pilot skill not biase and cry

mk 108 in BF-109G6a/s accuracy point is bad coz it shaking when compare to BF-109G-10 and "below 150 meter" range I said I mean snap short shooting coz 70% for shooting solution in DF-Server are deflection shooting

mk108 is my favor gun for over 3 years http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif
old hand deflection shoot... http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif (http://www.airwarfare.com/guides/deflection_guide.htm)

Stafroty
02-18-2006, 06:35 PM
Originally posted by Gibbage1:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by JG52Karaya-X:
Not if the usual trolls stay in bed - which I doubt http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif

Im already here. http://forums.ubi.com/images/smilies/784.gif </div></BLOCKQUOTE>

yes, already admitting that you are troll.
So, your motives for getting more realistic Simulation, we can forget. your motive have now understood for getting more biased and balanced game.

Stafroty
02-18-2006, 06:36 PM
Originally posted by Low_Flyer_MkVb:
Covering your six, Gib. http://forums.ubi.com/images/smilies/icon_twisted.gif

And here is another Troll, againt with clear BIAS towards something what they want, and that is not realistic simulation.

Stafroty
02-18-2006, 06:48 PM
Originally posted by Gibbage1:
Well it looks like nobod is willing too take a crack at this. I will start off things.

#1. What aspect do you think contribute too the Mk-108's remarkable accuracy?

Was its low velocity? How about its short berral? Maybe its extreamly light round in comparison too its size? Maybe its the very light aircraft it was attached too?

***Still points to remember which isnt good for you, its center of Cog in level, right in the middle of Prolellor, not in wings. all the recoil Force Gun makes, makes the Plane lost bit speed, all the recoil forces goes directly at the direcetion where the plane isnt moving. not up, not down. Not like with Rifle you shoot, if you dont have direct stock (with barrelline), like in Machineguns. Gun is Rifled, Ammo isnt round. and cannon was attached on engine, which was attached on airframe. For you, the Cannon is vibrating there like that ***** we talked earlier in some thread, and throwing ammo eve throught the engine, in some version, not even intrested anymore, that does the shots come out formt he sides as well now****

All these factors DONT contribute too a low dispersion, but CONTRIBUTE too its rather high dispersion!

*****of course, also long barrel has its effecet contribuing in effects of cannons, now much shorter is MK108 cannon barrel when compared to .50 cal barrel(42) .50cal (short one) has bout 53,3CM long barrel, how much does have MK108?****

#2. Have you done ANY testing on this, or are you here just posting your un-informed and rather un-biest openion? Should we trust your word that the dispersion is in fact rather bad?

****have you ever tested it? or always been on receiving end?*****

#3. What other proof do you have other then pilot openion? Im sure I can find a few pilot quotes to counter any you dig up about it being rather innaccurate, and they were just spraying what ammounted to a rappid fire grenade launcher in the area of a bomber formation in hopes something hits. How about German documents that list's the guns dispersion in mils?

*****Documents can others hunt/show*****

Stafroty
02-18-2006, 06:52 PM
Originally posted by Gibbage1:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by JG53Frankyboy:
install IL2 1.0 - there you will have your MK108 "sharpshooter" gun http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Or how about the Mk-103? Its got a much longer berral, greater charge, MUCH higher MV, and is a much heavier gun making it a more stable platform. All the ideal things for an accurate gun the Mk-103 DONT HAVE! </div></BLOCKQUOTE>


****you seem to Think, that cannon is there without bolted on something? yea? its detached on engine, count engine weight on it too. if we want to be more specific,s hould the cannon of the P39 37mm cannon be checked as well? its cannon isnt firing fast shots as well, maybe heavier but not fast.

or should always LW side guns be derated while others arent, just for balancing pilot skill factor? ****

Stafroty
02-18-2006, 07:07 PM
Originally posted by Gibbage1:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by JG5_UnKle:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Gibbage1:
There is an extreme lack of testing in this thread.

Well volunteered http://forums.ubi.com/images/smilies/clap.gif </div></BLOCKQUOTE>

I faught my fight for the .50 cal. I hate the Mk-108's so its not my fricken job to make them any better or worse. But I am not going too sit around and let a bunch of blue players say "Mk-108 not uber enough" and "Ja ja! Oleg fix it!" without proof since I am sure as he11 they would do the same in kind and DO the same when any similar Allied post's.

Without oposition, everyone here would agree the Axis won and the 109 was the best fighter ever http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif </div></BLOCKQUOTE>

is that .50whine all what have you did? and proud about it? you get it sound it as so.

The-Pizza-Man
02-18-2006, 07:11 PM
I think this has been gone over before Stafroty. The recoil of the Mk108 is huge compared other guns. It was something like 5-8 times what it is for that grenade launcher, ignoring recoil from the escaping gases, which is likely to be very significant with the Mk108 because of its short barrel.

I'd suspect at 800m that grenade launcher is firing against AREA targets. Against point targets it would probably be something of the order of 200-300 meters. The vehicle or tripod mounted M2HB .50 cal machine gun has a range of 2000 meters. It's effective range in WWII was historically quoted as being 300-600 meters. Your argument with the grenade launcher makes about as much sense as the guy who thinks pylon racers are an accurate evaluation of the relative performance of WWII fighters.

Nothing points to the Mk108 being an accurate weapon, more accurate than Hispanos, which what you were advocating in your previous thread on the topic. In fact, other people have done the tests on the Mk108 and compared it with real life data and found it to be more accurate than it should be. If you dispute this result, do the tests yourself. Until you actually do a scientific test and compare it with historical data of the same nature your argument that the Mk108 is inaccurate hasn't got a leg to stand on.

Stafroty
02-18-2006, 07:12 PM
and, i that 30mm bugs so much, why just not delete it totally, i dont care. would like if all guns from LW planes would have been taken out, half of the wings as well http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif i dont care. I think some of these forum jockeys would be happy finally to get kills from the ******* enemy, as it seems.

FritzGryphon
02-18-2006, 07:18 PM
The MK108, and dispersion of other guns, has been tested ad nauseum in previous years.

Here's some pics I made some time ago in PF. I have no reason to believe the disperion of any of these guns have changed as of late, so they should still be correct today.

The space between two lines indicates 10 mils, or 1 meter scatter at 100m range.

http://members.shaw.ca/evilgryphon3/mk108.jpg
13 mils
http://members.shaw.ca/evilgryphon3/mg131.jpg
8 mils

Gibbage1
02-18-2006, 07:18 PM
About time someone did a test.

10 mils hay? US test show the .50 cal is 15 mils at 300M. What should the Mk-108 be?

FritzGryphon
02-18-2006, 07:25 PM
At 100m Mk108: All shells should hit within an area of height 35 cm and width 30 cm.

If this is actually a real figure, it should only be 3-3.5 mils for the MK108. I would want to see the source first-hand, of course.


to the Mg131 installation in the G6/U4 the accuarcy requirement is height 100 cm and width 100 cm

The MG131, according to this data, should be 10 mils. Slightly larger than it is currently in game.

danjama
02-18-2006, 07:37 PM
Most boring thread of the year goes to this one...

FritzGryphon
02-18-2006, 07:50 PM
You're right. It's only fun if it's whining about .50cal dispersion!

Which is 8 mils btw, and exactly what it's supposed to be.

p1ngu666
02-18-2006, 08:08 PM
lol, page 3 and still no test of current patch, but hats off to fritz for posting those 2 pics http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

fritz could u post the mission and howto anazlize the results? i'd quite like to know http://forums.ubi.com/images/smilies/25.gif

Gibbage1
02-18-2006, 09:07 PM
Originally posted by FritzGryphon:
You're right. It's only fun if it's whining about .50cal dispersion!

Which is 8 mils btw, and exactly what it's supposed to be.

Your correct, 8 mils. In reality, 75% of the hits should be placed within 4 mils.

http://www.gibbageart.com/files/50s.jpg

Does anyone have any dispersion charts on the Mk-108? 100M is not a very good deturmination of its accuracy.

FritzGryphon
02-18-2006, 09:07 PM
In reality, 75% of the hits should be placed within 4 mils.


I agree, the distribution of the hits does not follow the real curve.

The game seems to randomly pick a vertical deviation, then a horizontal one, and combine them, which creates a square pattern.



I don't have the mission anymore, but I can describe it.

Make a tall structure. In this case, a row of smokestacks. It must be 100m *slant* distance from the guns of a sitting airplane. Set gun convergence to 100m.

Mark the lines 10m apart using barrage balloon cables.

Use arcade mode to see the hits. Fire with single shots and with brakes on, so the firing doesn't make the plane roll around.

carguy_
02-18-2006, 09:41 PM
Ok guys I see some dispersion screenies.

From which version of the game are those tests?

From which plane is the dispersion of 50cal shown?


First off,gentlemen, the screenie showing 4 mils features aircraft armed with 50cal IN THE NOSE.


Gibbage1 did something he will never admit.He pressed Oleg to change 50cal ballistics so the P38 could have point convergence.As a result he totally screwed up effectiveness of wing-armed 50cal aircraft such as P51 and P47.
Oleg stated that if the change Gibbage pressed for so long was to be made,ALL the 50cal guns were to be like on the P38 which means they would create POINT CONVERGENCE.On P38 or YP80 that have them in the nose it`s correct but what Gibbage failed to think about was that aircraft with 50cal in the wings would be hurt with point convergence to a MAJOR extent.


A point convergence made of six(that`s SIX) or eight 12.7mm Browning machineguns placed in wings make for a pathetic excuse of a weapon that was meant and entirely was in WWII to be used as a machinegun that would give enough dispersion to make those six(that`s SIX) or eight guns strike not at 4 mils point but at a close enough vicinity that makes them tracers form a box convergence so that maximum effectiveness can be acheved.
That applies for high deflection shooting,easiness of leading a shot and covering a desired frame with deadly hits.


Now anyone who has a problem with unvisible tracers or hitting with 50cal on P51/P47 should thank Gibbage for his fine effort of making 50cal something that was never meant to be used on wing armed heavy machineguns,only nose armed heavy machineguns namely pressing Oleg to make 50cal a point convergence weapon.


Now that doesn`t pose a biggie for me since I fly planes that Gibbage was unable to ruin.
I smile everytime when jumped by a P51 and missed from 100m.I know that in real life(where Gibbage has no influence) I (or at least my plane) would be full of holes.

People who fail to see the point convergence I speak to you.Do some tests and open your eyes on what Gibbage did to 50cal.


Yes Gibbage I know that you will from now on attack me whenever possible.I also know you`re that kind of person who is unable to admit he made a big mistake.You can post your mumbo jumbo to cover up your personal flaws.


As a gamer that is mostly on the other end of the fifties I sincerely hope that in BoB Oleg will model guns without participation of the likes of you. http://forums.ubi.com/images/smilies/clap.gif

danjama
02-18-2006, 09:44 PM
Originally posted by carguy_:
Ok guys I see some dispersion screenies.

From which version of the game are those tests?

From which plane is the dispersion of 50cal shown?


First off,gentlemen, the screenie showing 4 mils features aircraft armed with 50cal IN THE NOSE.


Gibbage1 did something he will never admit.He pressed Oleg to change 50cal ballistics so the P38 could have point convergence.As a result he totally screwed up effectiveness of wing-armed 50cal aircraft such as P51 and P47.
Oleg stated that if the change Gibbage pressed for so long was to be made,ALL the 50cal guns were to be like on the P38 which means they would create POINT CONVERGENCE.On P38 or YP80 that have them in the nose it`s correct but what Gibbage failed to think about was that aircraft with 50cal in the wings would be hurt with point convergence to a MAJOR extent.


A point convergence made of six(that`s SIX) or eight 12.7mm Browning machineguns placed in wings make for a pathetic excuse of a weapon that was meant and entirely was in WWII to be used as a machinegun that would give enough dispersion to make those six(that`s SIX) or eight guns strike not at 4 mils point but at a close enough vicinity that makes them tracers form a box convergence so that maximum effectiveness can be acheved.
That applies for high deflection shooting,easiness of leading a shot and covering a desired frame with deadly hits.


Now anyone who has a problem with unvisible tracers or hitting with 50cal on P51/P47 should thank Gibbage for his fine effort of making 50cal something that was never meant to be used on wing armed heavy machineguns,only nose armed heavy machineguns namely pressing Oleg to make 50cal a point convergence weapon.


Now that doesn`t pose a biggie for me since I fly planes that Gibbage was unable to ruin.
I smile everytime when jumped by a P51 and missed from 100m.I know that in real life(where Gibbage has no influence) I (or at least my plane) would be full of holes.

People who fail to see the point convergence I speak to you.Do some tests and open your eyes on what Gibbage did to 50cal.


Yes Gibbage I know that you will from now on attack me whenever possible.I also know you`re that kind of person who is unable to admit he made a big mistake.You can post your mumbo jumbo to cover up your personal flaws.


As a gamer that is mostly on the other end of the fifties I sincerely hope that in BoB Oleg will model guns without participation of the likes of you. http://forums.ubi.com/images/smilies/clap.gif

chill this aint for public eyes http://forums.ubi.com/images/smilies/compsmash.gif

Gibbage1
02-18-2006, 10:40 PM
Originally posted by carguy_:
Ok guys I see some dispersion screenies.

From which version of the game are those tests?

From which plane is the dispersion of 50cal shown?


P-39 Q-10 from 2.01



First off,gentlemen, the screenie showing 4 mils features aircraft armed with 50cal IN THE NOSE.


Wrong. Thats from the .50 cal manual and its for all .50 cal armed aircraft. Both wing and nose mounted. Let me type what it says in the gun manual that I got that pitchure from.

GUN HARMONIZATION

TYPES OF HARMONIZATION

Cones of Dispersion

In order to harmonize a fighter aircraft's guns to a definite pattern, it is neccessary to understand a gun's cone of dispersion. This cone of dispersion is the sum of all the flight paths of all the bullets fired from a gun. This dispersion is measured, in terms of mils, by the angle of the triangle formed from the muzzle of the gun to the diameter of the area of hits. The 4 mil cone is generally accepted and used for all harmonization computations. The cones of dispersion for ammunition of different calibers are not the same.

Note the bold text. Nose mounted guns dont use point harmonization anyways. This graphic applies to all harmonization computations!



Gibbage1 did something he will never admit.He pressed Oleg to change 50cal ballistics so the P38 could have point convergence.As a result he totally screwed up effectiveness of wing-armed 50cal aircraft such as P51 and P47.


Wrong. I tried to give the .50 cal ACCURATE DISPERSION! I got it. But then Oleg synced the guns on us. THAT screwed aircraft such as the P-51 and P-47. That much was proven in the recent patch, and the P-40E field mod before the patch.

Also, in IL2 pre-2.01 all guns BUT the .50 cal had EXTREME ACCURATE dispersion of 1-2 mils at 300M. It takes sniper rifles to get similar dispersion. The M2 .50 cal was calculated to having an 18 mil dispersion. It was ludicris to think all guns in WWII were sniper accurate, and the .50 cal was a total POS with the dispersion of an old shotgun. Dont try to twist the facts. Oleg also said there was no differance between the MG151/20 gunpods and nose cannon. He is a human and prone too error like the rest of us. Every patch proves that.



Oleg stated that if the change Gibbage pressed for so long was to be made,ALL the 50cal guns were to be like on the P38 which means they would create POINT CONVERGENCE.On P38 or YP80 that have them in the nose it`s correct but what Gibbage failed to think about was that aircraft with 50cal in the wings would be hurt with point convergence to a MAJOR extent.


No. You fail too understand that wing mounted guns were also had point convergence, and nose mounted guns did not need point convergence at all. Only horizontal convergance was needed. Do you need a refresher of what point convergence is? Its only used with wing mounted guns!



A point convergence made of six(that`s SIX) or eight 12.7mm Browning machineguns placed in wings make for a pathetic excuse of a weapon that was meant and entirely was in WWII to be used as a machinegun that would give enough dispersion to make those six(that`s SIX) or eight guns strike not at 4 mils point but at a close enough vicinity that makes them tracers form a box convergence so that maximum effectiveness can be acheved.


No. Syncronization made the .50's a pathetic weapon. Also extreme dispersion made them pathetic. Now they are a LOT more lethal. Again, the patch PROVES that it was not the tighter dispersion that messed up the .50's, but the syncing of the guns in 2.02. But your still ignoring that little fact, arnt you?



That applies for high deflection shooting,easiness of leading a shot and covering a desired frame with deadly hits.


Thats a part of de-syncing the guns, not fixing the dispersion.



Now anyone who has a problem with unvisible tracers or hitting with 50cal on P51/P47 should thank Gibbage for his fine effort of making 50cal something that was never meant to be used on wing armed heavy machineguns,only nose armed heavy machineguns namely pressing Oleg to make 50cal a point convergence weapon.


The patch fixed tracking by de-syncing the guns. Why would it be easier too track a wider dispersion anyways?



Now that doesn`t pose a biggie for me since I fly planes that Gibbage was unable to ruin.
I smile everytime when jumped by a P51 and missed from 100m.I know that in real life(where Gibbage has no influence) I (or at least my plane) would be full of holes.


You mean you fly the FW-190? The one aircraft that takes an extreme ammount of .50's to kill? The aircraft that takes 80+ hits into the engine before it stops? Thats not a function of the dispersion, but of the DM. You seem to eager to blame everything on me, you compleatly miss the truth. Your off by a wide margin.



People who fail to see the point convergence I speak to you.Do some tests and open your eyes on what Gibbage did to 50cal.


Ya. I fixed the dispersion from 18 mils to the proper 8 mils, and then I de-synced the guns. Now its a lot better to use in 4.03 and a lot more historical. What we had back in 2.01 was basically a shotgun. Now we have a proper stream of lead, and its DEADLY.



Yes Gibbage I know that you will from now on attack me whenever possible.I also know you`re that kind of person who is unable to admit he made a big mistake.You can post your mumbo jumbo to cover up your personal flaws.


You flatter yourself. I wont even remember your handle in a few moments. Hell, I dont even know who I am replying too. Just know that your totally wrong and spewing a bunch of ignorant BS and blaming me for everything. I have proven above that your full of SH and I dont mean Silent Hunter. The old dispersion was NOT HISTORICAL, and the synced guns where NOT HISTORICAL. I had those fixed, and now the .50's are a LOT more usefull. But there are some DM's that need to be tweaked.

[/quote]
As a gamer that is mostly on the other end of the fifties I sincerely hope that in BoB Oleg will model guns without participation of the likes of you. http://forums.ubi.com/images/smilies/clap.gif[/QUOTE]

So they can be un-historical? What would you rather have the .50's be like? Whats your version of what the .50's should be? Shotguns like we had them is what you want? I can see why, since they were total **** in deflection shooting.

BTW, I have not seen a single post that said the .50's are now worse. In fact, many many P-51 and P-47 pilots LOVE them now that they are de-synced. I also have not seen any Luftwaffe pilot saying they are now too uber. I guess with all that debate and me "forcing" Oleg to make them historical, we acheaved a rare balanced that Oleg has been stiving for. Unfortunatly there are a few ignorant people who dont read threads unless they involved the 109 or 190 like you. Open your eyes, read a few threads. You may learn something! Maybe, gasp, FLY AN ALLIED AIRCRAFT! Get a feel for it. See what its like and compare it to what it was.

With the tighter dispersion and desyncing of the guns, Allied pilots are far better off then the wide spread shotguns you seem to of loved. I wonder why a Luftwaffe pilot loved those old guns? http://forums.ubi.com/images/smilies/784.gif

Holtzauge
02-19-2006, 02:35 AM
Originally posted by FritzGryphon:
The MK108, and dispersion of other guns, has been tested ad nauseum in previous years.

Here's some pics I made some time ago in PF. I have no reason to believe the disperion of any of these guns have changed as of late, so they should still be correct today.

The space between two lines indicates 10 mils, or 1 meter scatter at 100m range.

http://members.shaw.ca/evilgryphon3/mk108.jpg
13 mils
http://members.shaw.ca/evilgryphon3/mg131.jpg
8 mils

Impressive test setup and presentation FritzGryphon. I myself am a rather sporadic sim pilot so the finer points of what can be done in PF are beyond me.

I think the results you show on the Mk108 dispersion in PF speak for themselves.....

Regarding the source material, this is from a copyrighted PDF publication from HAFNER luftarchiv so I'm not able to print any original material but I do believe that making quotes from this is OK:

This is taken from the Ta 152 H-0 and H1 FlugzeugHandbuch, Schusswaffenanlage, page 37:

I have taken the liberty to do a translation:

" Fire a burst of 11 rounds with MK 108. Determine the middle of the hit series. Adjust the Revi to coincide with the middle point"

My interpretation is since the MK108 is bolted to the engine and fires through the propeller hub then the Revi sight is adjusted to the nose gun and not the other way around as it is done for the other gun installtion.

After this follows direction on how to align the MK151 installation.

Then comes the section detailing the dispersion:

"Dispersion with the MK108 shall be (11 rounds fired):

H = 35 cm and B = 30 cm at a distance of 100m standard distance
H = 18 cm and B = 15 cm at a distance of <span class="ev_code_RED">50m</span> standard distance"

Note that it is not single rounds fired, but a "Feurstoss von 11 Schuss zu schiessen".

So these excerpts together with the test FritzGryphon posted pretty well sums it up. The modelling is off and should be corrected.

Q.E.D!

P.S: I can see the whining coming though, " How can we be sure you are not making all this up, this is just ONE document detailing the accuracy, there might be others that say something else, what PF version did you use in the test, was the sun coming in from left or right, what paint scheme did the a/c have, did you have a bun with your coffee before you did the test etc. etc. etc. http://forums.ubi.com/images/smilies/88.gif

Kocur_
02-19-2006, 03:21 AM
Field harmonisation device used in RAF 129Sq. equipped with Mustangs Mk.III. We see gunsight reference point and such for guncamera and four .50s. The latter are not in one horizontal line...
http://img113.imageshack.us/img113/8044/p51harmonization4ay.png (http://imageshack.us)

Kocur_
02-19-2006, 03:24 AM
Gib! When was that gun instruction published? I see P-80 there.

Kocur_
02-19-2006, 03:43 AM
Originally posted by The-Pizza-Man:
The recoil of the Mk108 is huge compared other guns. It was something like 5-8 times what it is for that grenade launcher, ignoring recoil from the escaping gases, which is likely to be very significant with the Mk108 because of its short barrel.


Both of those weapons are API blowback operated, so we can safely assume both projectiles momentum is enough to judge relative recoils:
AGS-17: 30mm VOG-30
275g, 185ms, 50kgms

MK108 Minengeschoss
330g, 505ms, 166kgms

166/50 = 3,3

I.e. dont fire MK108 from AGS-17 tripod, but the guns recoil was not a reason for it to disperse alot. What matters is weight not of sole gun, but gun+mounting. And its tens of kg in case of AGS-17 and thousands in case of MK108 - as it was fixed with engine, which was fixed inairframe.

The "recoil from the escaping gases" is gun gas rocket effect. It is present in all guns, but affects less those blowback or API blowback operated, as bolt is not fixed with barrel when rocket effect workes - unlike guns where bolt is locked with barrel, directly or not directly, i.e. via receiver.


Anyway whole discussion (if there is any) about dispersion of MK108: fine or too large in game is pointless, assuming one belives the document is authentic, since there are no technical reasons not to find what it says perfectly credible.

Kurfurst__
02-19-2006, 04:16 AM
Originally posted by Gibbage1:
Well it looks like nobod is willing too take a crack at this. I will start off things.

#1. What aspect do you think contribute too the Mk-108's remarkable accuracy?

Was its low velocity? How about its short berral?

Low velocity and short barrel is very good achieve low dispersion on an automatic weapon - there's less of a barrel vibration and flexing, something you can't avoid on long barrels, especially if a high-energy rounds is passing through every 1/10th of a second..

An importany aspect of low-velocity guns is that they dont come with nearly as much wear on the barrel liners. High MV guns wore out the barell quickly, and dispersion detoriates fast...




Maybe its extreamly light round in comparison too its size?

330-370gram is anything but light for a 30mm round.


Maybe its the very light aircraft it was attached too?

The MK 108, at least on the Bf 109, was not attached to the aircraft but a 800+kg hump of metal block, called the engine. That's the best place to mount a weapon, since it's much more rigid than flexing wings, for example. In wing mountings, though these were rarely used, it should be worser.


All these factors DONT contribute too a low dispersion, but CONTRIBUTE too its rather high dispersion!

You have no idea on this.



How about German documents that list's the guns dispersion in mils?

I have one. It compares the 20mm MGFF, MG151/20, and the 30mm MK 108 and MK 103.
Surprise surprise, the least powerful, shortest barreled MG FF has the tightest disperison pattern of 1 mil, followed by the MK 108, and then the long barelled MG 151 and the extremely powerul, extremely high velocity, long barreled MK 103 closes the line with 2 mils dispersion.



Another one was posted a good while ago by butch2k at AAW.

Kocur's estimate was excellent, ie. 3.3 vs. 3.5mils dispersion of the real thing. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif



Originally posted by Butch2k on AAW :
http://www.allaboutwarfare.com/forums/index.php?showtopic=492&hl=dispersion

Here are the results of a lenghty research into dispersion data, which is quite hard to come by...
The data is based on 100% diameter dispersion with 1 mil = 1/1000th of rad, the kind of mount is precised next to the weapon. 75% dispersion diameter is supposed to be half the 100% diameter which seems quite true for most weapons, this value is provided when quoted in the source (M2 data for instance).

We can clearly see the impact of the wing mounting compared to engine mounting, the later seems to have absorbed recoil and vibration much better... indeed dispersion is at least 2 times greater with wing mounted weapons.
Engine mount are the most efficient but nose mounting or cowling mounting does not provide the same amount of precision the mount being much more prone to vibration it seems.

Note that US data on the M2 is confusing since the reference data comes from a P-38 nose mounted M2, but the US manuals use the same dispersion data for wing mounted weapons. Either the P-38 mounts are really up to no good or the manuals make a wrong assumption when it comes to wing dispersion. I tend to believe the later, i think the wing mounted M2 would have had a dispersion of at least 12mils and probably more.

If you quote this data on other sites/bbs please precise the source being AAW. TIA

H means Height (or max dispersion diameter) as i previously used vertical and lateral dispersion values.

D means distance.

Units are metric.

German Weapons
-----------------------
MG-17 Cowling mounted (Bf 109F-2 / Bf 109F-1 actual tests)
H = 0.60 / 0.8 m
D = 100 m
R/D = 60/10000 80/10000
= 6 mils / 8 mils

MG-131 Cowling mounted (Fw 190A - theorical max)
H = 1m
D = 100m
H/D = 100/10000
= 10 mils

MG-151/15 Engine mounted (Bf 109F-2 actual test)
H = 0,35 m
D = 100 m
H/D = 35/10000
= 3.5 mils

MG-FF Engine mounted (Bf 109F-1 actual test)
H = 0,2 m
D = 100m
H/D = 20/10000
= 2 mils (very tight patern)

MG-FF Wing mounted (Bf 109E-3 actual test)
H = 0,35 m
D = 100m
H/D = 35/10000
= 3.5 mils

MG 151/20 Engine mounted (Bf 109G-6 - theorical max)
H = 0.3m
D = 100m
H/D = 30/10000
= 3 mils

MG 151/20 Wing mounted - inner (Fw 190A - theorical max)
H = 0.7m
D = 100m
H/D = 70/10000
= 7 mils

MG 151/20 Wing mounted - outer (Fw 190A - theorical max)
H = 0.8m
D = 100m
H/D = 80/10000
= 8 mils

MK 108 Engine mounted (Ta 152 - therorical max)
H = 0.35
D = 100m
H/D = 35/10000
= 3.5 mils

Allied Weapons
------------------
M2 Nose mounted P-38 (USAAF 1944 Gunnery manual)
H = 1.88 m
D = 229 m
H/D = 188/22900
= 8.2 mils (75% = 4.1 mils)

Hispano 20mm Nose mounted P-38 (USAAF 1944 Gunnery manual)
3 mils 75%
6 mils 100% assumed






Now I'd like to see the MK 108 and .50s match their historical accuracy (or the lack of it)...

Kocur_
02-19-2006, 04:28 AM
Kocur's estimate was excellent, ie. 3.3 vs. 3.5mils dispersion of the real thing.
My what? http://forums.ubi.com/images/smilies/blink.gif

Kurfurst__
02-19-2006, 04:35 AM
oh, i was thinking you were making an estimate from a similiar gun with known dispersion values... my bad, sorry.

Gibbage1
02-19-2006, 05:07 AM
Originally posted by Kurfurst__:

Now I'd like to see the MK 108 and .50s match their historical accuracy (or the lack of it)...

The .50 cal already does. Its at 8 mil 100%. Unfortunatly with IL2's poor dispersion simulation, we cant get the 4 mil 75%.

As for the manual, it was was printed in 1948. It has the F-82, F-80 and F-84 charts in it. It also has the AP penetration charts. Very nice book. The M2 did not change from 1944 too 1948, just the aircraft that carried it.

Stafroty
02-19-2006, 05:16 AM
Kurfurst__ Wrote:

I have one. It compares the 20mm MGFF, MG151/20, and the 30mm MK 108 and MK 103.
Surprise surprise, the least powerful, shortest barreled MG FF has the tightest disperison pattern of 1 mil, followed by the MK 108, and then the long barelled MG 151 and the extremely powerul, extremely high velocity, long barreled MK 103 closes the line with 2 mils dispersion.

are these values from single shots used witht these guns, but not the burst accuracy? is there any information about this? http://forums.ubi.com/groupee_common/emoticons/icon_redface.gif

Its funny how people assume the wonder weapon to be most accurate, over cannons.. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif why dont they make .50cal rail guns with no barrel wear and muzzle velocity faster than sound throught the ammo metal itself, it would lead perfect penetration, as metal would influx itself with the target metal, at those speeds (some 5000m/sec est.)

Gibbage1
02-19-2006, 05:22 AM
Originally posted by Stafroty:
Its funny how people assume the wonder weapon to be most accurate, over cannons.. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif why dont they make .50cal rail guns with no barrel wear and muzzle velocity faster than sound throught the ammo metal itself, it would lead perfect penetration, as metal would influx itself with the target metal, at those speeds (some 5000m/sec est.)

What are you trolling about now? Nobody mentioned anything like that.

Also take note that all German test's are done at 100M, and all Allied test done at 300M. The longer the range, the more dispersion since the shells are effected by more elements during there flight path.

But thats good old Kurfy trying to slip one under us. Like a nice Lawyer.

Kocur_
02-19-2006, 05:24 AM
As for the manual, it was was printed in 1948. It has the F-82, F-80 and F-84 charts in it. It also has the AP penetration charts. Very nice book. The M2 did not change from 1944 too 1948, just the aircraft that carried it.

Well, those aircrafts didnt have their guns mounted in the way they were mounted in P-40, P-47 or P-51. Even central wing between P(F)-82 fuselages would be different than outer wings of above WW2 planes, no to mention noses of F-80 and 84.

Just after WW2 M2 was replaced by M3 - derivative of previous with higher ROF. I dont know if F-82 and F-80 got them, but Im convinced that F-84 had them (like F-86). I wonder also if M2s were replaced with M3s in all planes.

Gibbage1
02-19-2006, 05:30 AM
Originally posted by Kocur_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">As for the manual, it was was printed in 1948. It has the F-82, F-80 and F-84 charts in it. It also has the AP penetration charts. Very nice book. The M2 did not change from 1944 too 1948, just the aircraft that carried it.

Well, those aircrafts didnt have their guns mounted in the way they were mounted in P-40, P-47 or P-51. Even central wing between P(F)-82 fuselages would be different than outer wings of above WW2 planes, no to mention noses of F-80 and 84.

Just after WW2 M2 was replaced by M3 - derivative of previous with higher ROF. I dont know if F-82 and F-80 got them, but Im convinced that F-84 had them (like F-86). I wonder also if M2s were replaced with M3s in all planes. </div></BLOCKQUOTE>

P-84 shows both nose mounted and wing mounted guns.

It also mentions F-47, F-51D and H, F-80 and F-84 had M2 with athe F-80 and F-84 being M3 optional.

It also has all sorts of charts for the P-51 and P-47 in it. IT seems to be a mis-mosh of the 1944 manual with updated 1948 stuff in it.

But if it was for the M3, dont you think it would have more dispersion then the M2 due too the much greater ROF?

Kocur_
02-19-2006, 05:59 AM
Originally posted by Gibbage1:
But if it was for the M3, dont you think it would have more dispersion then the M2 due too the much greater ROF?

No, not really. M3 was basically a M2 with lighter moving parts and minor changes in details. More dispersion would have come from greater co-axial clearance of barrel mounting in receiver - as those weapons were recoil operated their barrels moved back and forth in receiver, which means some clearance. But nothing indicates such a difference between M2 and M3, so I think dispersion of both weapons was similar.

Aaron_GT
02-19-2006, 06:17 AM
Ya. I fixed the dispersion from 18 mils to the proper 8 mils, and then I de-synced the guns.

Given that you must have access to the code since you did this could you fix the Tempest speeds too?

Stafroty
02-19-2006, 06:36 AM
Originally posted by Gibbage1:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Stafroty:
Its funny how people assume the wonder weapon to be most accurate, over cannons.. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif why dont they make .50cal rail guns with no barrel wear and muzzle velocity faster than sound throught the ammo metal itself, it would lead perfect penetration, as metal would influx itself with the target metal, at those speeds (some 5000m/sec est.)

What are you trolling about now? Nobody mentioned anything like that.

Also take note that all German test's are done at 100M, and all Allied test done at 300M. The longer the range, the more dispersion since the shells are effected by more elements during there flight path.

But thats good old Kurfy trying to slip one under us. Like a nice Lawyer. </div></BLOCKQUOTE>

***Say, when you shoot at HMG at long distance, like at 300m, is that long distance for munition, like .50cal, or 30mm to be affected with wind SO much? you even been shooting with assault rifle at that distance?? wind isnt affecting THAT MUCH on the result. Seems you are virtually learned how to shoot with guns, have you ever been shooting rifles in wind, seeing how much rounds are affected with between 200m range.. if you have 35cm dispersion at 100m range, doesnt it be 70cm at 200? and that is with 11 rounds Burst with 30mm, not single shot like in your tests.****

thats good old gibbage trying to prove his already known bias.

(you like that last comment i said, ABOUT you? can we drop things like that?)

p1ngu666
02-19-2006, 08:16 AM
still no test http://forums.ubi.com/images/smilies/34.gif

Stafroty
02-19-2006, 10:00 AM
are you do hopeless pingu, that you cannot test it by yourself. if i bring you graphs which are pointhing BS, not even the truth in game, it still would make you believe in those, right?

p1ngu666
02-19-2006, 10:48 AM
yep im hopeless.

still u want me to make a map, then test the dispersion for you, dont u?

could turn out the mk108 is a lazer, or that its as acurate as me with a heavy machinegun irl

if oleg read this thread he would find hardly anything useful

if someone else does some testing, then so will i

Stafroty
02-19-2006, 09:18 PM
Pingu, whats your important post in this Thread? or are as important as this is?

Gibbage1
02-19-2006, 09:27 PM
Originally posted by Stafroty:
Pingu, whats your important post in this Thread? or are as important as this is?

This is rather ironic comming from a troll. Whats your contrabution? Have you done any testing? Have you found any dispersion info on the gun?

jermin122
02-19-2006, 09:57 PM
[QUOTE]Originally posted by Gibbage1:
100M is not that far away. If your 100M frm an enemy bomber, your taking hits. The Mk-108 was fired at MUCH greater distances then that.

QUOTE]

If 108 can hit bombers form that far, doesn't it just prove that its dispersion is very low?

jermin122
02-19-2006, 10:19 PM
It is interesting to note that most of posts calling for a tests and proof are the ones most devoid of any facts but filled to the brim with biased unsubstantiated opinions.

Dont take him too seriously. He knows nothing but just want to pretend to be an expert.

Gibbage1
02-19-2006, 10:22 PM
Originally posted by jermin122:

If 108 can hit bombers form that far, doesn't it just prove that its dispersion is very low?

No. Thats what the high ROF was for. Please read 109 and 190 pilots accounts of using that thing in a bomber formation. They would aim in the general direction and spray into the box in hopes to contact something, and stay away from the gunners. It was a standoff weapon. You dont need a very low dispersion to shoot a bomber formation. You need it for shooting down small dodging fighters.

jermin122
02-19-2006, 10:48 PM
Dont just wait there and ask sb else to do the test, it was you Allied whinners that raised the opposite opinions. You should provide the evidences. The facts has proved that you LW whinners do nothing besides know nothing. Do you really love this sim, I dont think so, cuz you never play this sim seriously.

Gibbage1
02-19-2006, 11:54 PM
Originally posted by jermin122:
Do you really love this sim, I dont think so, cuz you never play this sim seriously.

Lol. Great logic. Hahahaha. Wow. Nice troll.

Like I said, when I tried to fix the .50's, I had too provide a LOT of proof. Now its your guys turn.

I already faught my battle. I dont use the noob cannon so I have no need to make it any better or worse.

The-Pizza-Man
02-20-2006, 12:52 AM
Originally posted by Kocur_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by The-Pizza-Man:
The recoil of the Mk108 is huge compared other guns. It was something like 5-8 times what it is for that grenade launcher, ignoring recoil from the escaping gases, which is likely to be very significant with the Mk108 because of its short barrel.


Both of those weapons are API blowback operated, so we can safely assume both projectiles momentum is enough to judge relative recoils:
AGS-17: 30mm VOG-30
275g, 185ms, 50kgms

MK108 Minengeschoss
330g, 505ms, 166kgms

166/50 = 3,3

I.e. dont fire MK108 from AGS-17 tripod, but the guns recoil was not a reason for it to disperse alot. What matters is weight not of sole gun, but gun+mounting. And its tens of kg in case of AGS-17 and thousands in case of MK108 - as it was fixed with engine, which was fixed inairframe.

The "recoil from the escaping gases" is gun gas rocket effect. It is present in all guns, but affects less those blowback or API blowback operated, as bolt is not fixed with barrel when rocket effect workes - unlike guns where bolt is locked with barrel, directly or not directly, i.e. via receiver.


Anyway whole discussion (if there is any) about dispersion of MK108: fine or too large in game is pointless, assuming one belives the document is authentic, since there are no technical reasons not to find what it says perfectly credible. </div></BLOCKQUOTE>

I did the calculation in another thread. Multiply your numbers by the respective rates of fire and it gives you an average recoil force while the weapon is firing. The peak recoil of the Mk108 would be even higher than 5-8.

Anyhow, the low muzzle velocity and sectional density of the Mk108 round would have a pretty negative effect on accuracy. From a technical perspective I can't see it being of the same level of accuracy as the Hispano, M2 or MG151 at anything over 150 meters. Pilot accounts tend to support this.

But the thing that is lacking here are tests. If Stafroty wants to continue to whine about Mk108 accuracy then he needs to do the tests.

Stafroty
02-20-2006, 02:40 AM
From Gibbage:
" i dont use the noob cannon so I have no need to make it any better or worse."

sure, why are you here then? you just pointed out that you urself are only a troll, with no information or anything else. you afraid something and thats why you are here, and we all know what.

from Gibbage:

"They would aim in the general direction and spray into the box in hopes to contact something, and stay away from the gunners."

What does this prove about weapon accuracy?
does that prove more that pilots werent suicidal like virtual pilots tend to be.
how carefully would you fly this sim, if you only got one virtual life in it, if you die, game would not work anymore.


from The-Pizza-Man:
"Anyhow, the low muzzle velocity and sectional density of the Mk108 round would have a pretty negative effect on accuracy. From a technical perspective I can't see it being of the same level of accuracy as the Hispano, M2 or MG151 at anything over 150 meters. Pilot accounts tend to support this."

i would like to see your pilot accounts, when compared to Hispanos, which there is 4x in hurricane, and in 2 in spit, and 4 in tempest, they have over 200 000KJ total recoil energy, compared to MK108 which has 84 000KJ recoil energy, just counted from ammo weight and muzzle velocity. If we count the rate of fire per sec also in here, hispanos would have some mm, 3 times bigger Recoil than MK108 have. and Mk108 isnt on wings. and, i think your technical perspective is quite limited, as well. care to share those calculations?

p1ngu666
02-20-2006, 09:22 AM
Originally posted by Stafroty:
Pingu, whats your important post in this Thread? or are as important as this is?

well, u have the one of the most important posts, as u are the topic starter, and others have inputed some data, are my posts more important than that one? nope. more imporant than the one above im quoting http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

jermin, the gun could have all the dispersion in the world and still hit bombers, just a matter of time http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

its amusing to note, your saying that me and gibbage especial, who are aprently biased trolls etc, should do all the research and testing, does that REALLY sound like a good idea?

i will test it, if someone else does. if only 1 tests, then they could fake it. and id bet you would find fault with any test me or gibb did.

i might be going on holiday in the next day or so, so that might stop me testing http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

oh and in the tests i did for your mk108 recoil whine thread, mk108 can barely move 109, or 190
20mm hispano's, in the hurri IIC could propell it to some 50kph. im going off my shakey memory but hey http://forums.ubi.com/images/smilies/16x16_smiley-tongue.gif

Kocur_
02-20-2006, 10:13 AM
Originally posted by The-Pizza-Man:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Kocur_:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by The-Pizza-Man:
The recoil of the Mk108 is huge compared other guns. It was something like 5-8 times what it is for that grenade launcher, ignoring recoil from the escaping gases, which is likely to be very significant with the Mk108 because of its short barrel.


Both of those weapons are API blowback operated, so we can safely assume both projectiles momentum is enough to judge relative recoils:
AGS-17: 30mm VOG-30
275g, 185ms, 50kgms

MK108 Minengeschoss
330g, 505ms, 166kgms
166/50 = 3,3


I.e. dont fire MK108 from AGS-17 tripod, but the guns recoil was not a reason for it to disperse alot. What matters is weight not of sole gun, but gun+mounting. And its tens of kg in case of AGS-17 and thousands in case of MK108 - as it was fixed with engine, which was fixed inairframe.

The "recoil from the escaping gases" is gun gas rocket effect. It is present in all guns, but affects less those blowback or API blowback operated, as bolt is not fixed with barrel when rocket effect workes - unlike guns where bolt is locked with barrel, directly or not directly, i.e. via receiver.


Anyway whole discussion (if there is any) about dispersion of MK108: fine or too large in game is pointless, assuming one belives the document is authentic, since there are no technical reasons not to find what it says perfectly credible. </div></BLOCKQUOTE>

I did the calculation in another thread. Multiply your numbers by the respective rates of fire and it gives you an average recoil force while the weapon is firing. The peak recoil of the Mk108 would be even higher than 5-8. </div></BLOCKQUOTE>

Im affraid you are wrong on recoil here. Calculation of projectiles momentum, for a single shot or a burst, is not recoil yet. It can serve for comparison between two guns, assuming both have the same principle of operation, but it takes including weapon weight to learn anything on actual energy of recoil.
There are two phases of recoil: first beginning at the moment when projectiles starts to move in barrel and ending when it leaves muzzle. It is here that projectile momentum and guns weight are enough to calculate force of recoil. Simply divide projectile momentum by gun weight to get velocity of recoiling gun. Having that and gun's weight just use KE equation to learn energy of recoil.
The second phase of recoil begins at the moment of projectile leaving muzzle and lasts until pressure in barrel drops to athmospherical. In that phase recoil is increaced by gun gas leaving barrel and making it work like a rocket motor. This one is not so easy to calculate - and it is a topic for a longer lecture. Basically forces created in this phase are smaller than in 1st phase, because were dealing here with weight of propellant instead of projectile's.

Now AGS-17 and MK-108 recoils are incomparable. We must deal with weight of gun and its mounting. If we decide to drop gun gas effect part of recoil (2nd phase) for the sake of clarity, we will have:

AGS-17 projectile:275g, 185ms. Weight of gun+mounting: 30kg. So:

0,275 x 185 / 30 = 1,67ms of recoil velocity, thus

1,67^2 x 30 x 0,5 = 47J of recoil energy

MK108 projectile: 330g, 505ms.l Weight of gun+mounting... about 2,300kg in case of Bf-109, for MK108 was fixed in airframe (guess dispersion was tested with an empty plane)!


0,330 x 505 / 2300 = 0,072ms of recoil velocity, thus

0,072^2 x 2300 x 0,5 = 6J of recoil energy!


So whatever part of AGS-17 dispersion is caused by recoil - much smaller was responsible for that in case of NK108 ground dispersion test!




Anyhow, the low muzzle velocity and sectional density of the Mk108 round would have a pretty negative effect on accuracy. From a technical perspective I can't see it being of the same level of accuracy as the Hispano, M2 or MG151 at anything over 150 meters. Pilot accounts tend to support this.



Not assuming you confuse them, but to clarify again and get rid of confusion: dispersion is not equal to, lets call it "practilcal accuracy", i.e. probability of hitting a target. Imagine MK108 and a heavy machinegun fixed to big concrete stands. Both are perfectly aimed at their targets, i.e. proper elevation is used for both for distance to targets was precisely measured. Mk108 will present in that test better dispersion (due to stiffer barrel and heavier projectile - basically). Does that mean, that from PRACTICAL user's POV MK108 is more "accurate"? No!
It is so beacause practical user has to set proper elevation himself. To do that he must judge distance to target properly. And here MK108 will be less "accurate" for sure! For it has low MV, which dictates high arched trajectory, i.e. maximum ordinate at any distance will be greater than for hmg.

If one wants to hit a target at a certain distance he has to set proper elevetion, i.e. angle at which he will have his weapon pointed upwards, so that he trajectory end will be on target. Change of angle makes change in trajectory shape. One changes angle of elevation judging distance to target: the further he thinks it is, the higher angle of elevation he will set.

In case of flat trajectory weapon differences of trajectories made by different angles of elevation, i.e. by shooter estimation of distance to target are small:
http://img479.imageshack.us/img479/9134/molow1la.th.jpg (http://img479.imageshack.us/my.php?image=molow1la.jpg)

The shooter wanted to hit the point in upper part of front wall of the green box. He estimated distance to target before first shot, set elevation he though was proper and fired. He hit a bit too low. At second time he set bigger elevation and hit the spot. At third time set even bigger elevetion and still hit the target. Note how different were angles he chosed - yet still hit the target.
Flat trajectory - one can make big mistakes in estimation of distance to target, i.e. mistakes in angle of elevation and still hit.


Now high arched trajectory weapon:
http://img479.imageshack.us/img479/6051/mohigh5lx.th.jpg (http://img479.imageshack.us/my.php?image=mohigh5lx.jpg)

At first time the shooter estimated distance to target too low, so set too low angle of elevation - and missed. At second time made very little change of elevation - and this time elevation was proper for the distance, so he hit. At third time he set elevation a little bit higher - as if target was a bit further, and that little change made big difference in trajectory, so he missed.
High arched trajectory - making little mistakes in estimation of distance to target, i.e. little mistakes in angle of elevation - causes missing.


What made pilots discribe MK108 as "inaccurate weapon" was high arched trajectory, which meant that if they made far smaller errors in elevation than in case of hmg or 20mm cannons, they missed firing MK108. MK108 dispersion was low, but that didnt matter much when it came to practical shooting. Again: dispersion is not equal to accuracy. Dispersion is a part, and not a major part, of accuracy when it comes to comparing a weapon of flat trajectory and one of high arched trajectory.

(sorry for lousy pics http://forums.ubi.com/images/smilies/35.gif)

Holtzauge
02-20-2006, 01:01 PM
A nice explanation on the difference of accuracy and dispersion Kocur_

I totally agree with the point make about the MK108 ability to engage targets at a distance. I guess that was why the Germans were in search of weapons with greater range and shorter time of flight: to stay out of the effective range of the defensive fire of the bombers and increse the probability of hits. For the average pilot, it would be difficult to attain a hit at long range but we are talking about 100m here!

Being a hunter, I am well aware on the importance of muzzle velocity to increse chances of hitting at target. To your explanation I would like to add the importance of keeping your rifle/MK or wahtever from leaning. If the shhoting platform is angled, the shot will, due to the need to angle it up, go to the side and low. This is something any hunter knows and why a high velicoty rifle is more forgiving. The MK108 will suffer more in this respect than the Hispano for example.

However, I want to see historical dispersion on the Mk108 because as, FritzGryphons test showed, a Mk108 round could land OUTSIDE a 1 x 1 m square even at 100 m range even PERFECTLY aimed. Now this means that a shell even PERFECTLY aimed could miss a fuselage in the game at 100m. Is this historical? A IRL German pilot missing an a/c flying dead ahead steady at a 100m range would probably kill the mechanic (with good reason) on landing.

All ye doubter go to view F2 external and take a look at how a Me 109 rocks when the Mk108 is fired. Download some IRL gun cams from Me 109's and study the tracer. IT IS LIKE A HOSE! THE ROUNDS ARE STEADY AS A ROCK. This is what you get if you:

1) Put the axis of fire in the centerline
2) Put the axis of fire in/almost through the C.G
3) Bolt the gun to a solid with a ton weight.

No rocket science. Just plain common sense (not always found in abundance in some of the post above). http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

DaimonSyrius
02-20-2006, 01:21 PM
Originally posted by Kocur_:
If one wants to hit a target at a certain distance he has to set proper elevetion
.../...
(sorry for lousy pics http://forums.ubi.com/images/smilies/35.gif)
Kocur,

Never mind about aesthetical perfection, your pictures are splendid in that they illustrate very well the relevant aspects of elevation, i.e., flat(er) vs. arched trajectory with regards to accuracy in aiming and, especially, the impact on aim correction. They are the best I've seen about this specific issue (moreover, I haven't really seen this issue presented in clear graphs before). Well done, and thanks for your excellent post http://forums.ubi.com/images/smilies/clap.gif http://forums.ubi.com/images/smilies/clap.gif

I'd like to contribute a couple of pictures and references about gunnery and ballistics, only to add them to this thread, so that anyone interested in the subject can more conveniently have a comprehensive view of it.

Trajectory drop and gunsight line:
http://www.infonegocio.com/daimon/img/Trajectory-drop.gif

Harmonisation (in wing-mounted guns):
http://www.infonegocio.com/daimon/img/Harmonisation.gif

I've taken these images from The WWII Fighter Gun Debate: Ballistics (http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fgun-th.html)
Home page here: The WWII Fighter Gun Debate: Introduction (http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fgun-in.html)

Another comprehensive source: CANNON, MACHINE GUNS AND AMMUNITION (http://www.quarry.nildram.co.uk/index.htm)

And finally, PE_Mosor's IL2-specific site: http://free-st.htnet.hr/dvd/

Cheers,
S.

p1ngu666
02-20-2006, 01:28 PM
rock steady nose cannon in action http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

http://www.tarrif.net/wwii/movies/bf109g_vs_spitfire.wmv

http://forums.ubi.com/images/smilies/59.gif

http://www.tarrif.net/wwii/movies/index.htm

the other ones are stable tho http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Stafroty
02-20-2006, 01:56 PM
Originally posted by p1ngu666:
rock steady nose cannon in action http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

http://www.tarrif.net/wwii/movies/bf109g_vs_spitfire.wmv

http://forums.ubi.com/images/smilies/59.gif

http://www.tarrif.net/wwii/movies/index.htm

the other ones are stable tho http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

see how it looks like rounds go up just because the shooting plane is moving down, its not the same as you would be shooting with machinegun belt full of tracers as gunner stays still. there, plane and camera moves, so it means, they arent static in horizontally. and how fast you think is that film running?

Xiolablu3
02-20-2006, 02:37 PM
None of those are firing mk108 are they?

That Spitfire looks like its hit with 20mm as they wings dont look too damaged when they are hit.

Gibbage1
02-20-2006, 02:40 PM
Looked like some rather nasty recoil on that.

If the spitfire was manuvering down, you would see the tail come up.

Allied_Killer
02-20-2006, 03:52 PM
Originally posted by Gibbage1:
Looked like some rather nasty recoil on that.

If the spitfire was manuvering down, you would see the tail come up.

You is wrong, those were nasty wobbles, be sure!!!

The-Pizza-Man
02-20-2006, 04:19 PM
i would like to see your pilot accounts, when compared to Hispanos, which there is 4x in hurricane, and in 2 in spit, and 4 in tempest, they have over 200 000KJ total recoil energy, compared to MK108 which has 84 000KJ recoil energy, just counted from ammo weight and muzzle velocity. If we count the rate of fire per sec also in here, hispanos would have some mm, 3 times bigger Recoil than MK108 have. and Mk108 isnt on wings. and, i think your technical perspective is quite limited, as well. care to share those calculations?

Do you have amnesia or are you being deliberately dishonest? I did them in the other thread you started on the topic. As someone who talks about recoil the way you do I find your opinion on the techical aspects of this debate pretty worthless.

If you want to make a legitimate argument for an inaccurate Mk108 then you need to do the tests and compare it against historical data. Until you do that you have NFI what is correct. Your just trolling unless you do the tests.

p1ngu666
02-20-2006, 07:14 PM
wonder if this will push it onto 6 page http://forums.ubi.com/images/smilies/halo.gif

that one i picked out has some wobbling in the vertical http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Stafroty
02-21-2006, 06:45 AM
Originally posted by Gibbage1:
Looked like some rather nasty recoil on that.

If the spitfire was manuvering down, you would see the tail come up.

see that background? see how fast the parts of the spits are coming towards camera?
that kind of aluminium strips lose their speed quite rightaway as they dont have much Ke and have Lots of drag.

Holtzauge
02-21-2006, 10:28 AM
Originally posted by p1ngu666:
rock steady nose cannon in action http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

http://www.tarrif.net/wwii/movies/bf109g_vs_spitfire.wmv

http://forums.ubi.com/images/smilies/59.gif

http://www.tarrif.net/wwii/movies/index.htm

the other ones are stable tho http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Pingu my man, very illuminating! You have just demonstrated what happens when you wave a hose up and down and not hold it steady! Do it all the time in my garden. Totally to the point and very consistant with the point I was trying to make! Muchos gracias!

Seeing your previous posts I know you like to see tests of everything.To convince you about validity, I suggest you perform this test yourself.

Test setup: Drink some coffee, wait for the effects, take a steady grip (if it's not to short), aim and fire. You should now see a steady stream. Wiggle it some to try and align the stream to your target. You should get about the same effect as in the flick. Please post results! Best of luck!

Blutarski2004
02-21-2006, 10:40 AM
Originally posted by Kocur_:
What made pilots discribe MK108 as "inaccurate weapon" was high arched trajectory, which meant that if they made far smaller errors in elevation than in case of hmg or 20mm cannons, they missed firing MK108. MK108 dispersion was low, but that didnt matter much when it came to practical shooting. Again: dispersion is not equal to accuracy. Dispersion is a part, and not a major part, of accuracy when it comes to comparing a weapon of flat trajectory and one of high arched trajectory.


..... Thank you, Kocur - you are a voice of reason in a sea of uninformed debate.

Let me reinforce your point. This is another issue which was discussed, decided, and put to rest about two years ago, right down to a graph of the original LW ballistic data related to the MK-108 as installed in the 109-G6. The original is still presumably somewhere in the Zoo archives. I'm working from a hard copy in my file.

Three weapons are displayed on the document, which dicussed projectile flight path relative to the gunnery sight line:

MG 131 (engine-mounted)
MK 108 (cowling-mounted)
MG151/20 (presumably gondola-mounted)

MG 131 mounted 30 cm below sight line.
MK 108 mounted 80 cm below sight line.
MG 151/20 mounted 120 cm below sight line.

To established a more or less equal basis for comparison, a comparison wil be drawn of the distances between the first cut and the seconf cut of the sight line by the projectile path of each gun.

MG 131 .......... 360 M (40 to 400 M)
MG151/20 ........ 360 M (140 to 500 M)
MK 108 .......... 320 M (80 to 400 M)

Note the excellent ballistic match between the MG 131 and the MG 151/20. The engine-mounted MG 151/20 combined extremely well with the MG 131 to produce a dense hitting pattern between about 100 and 400 meters - similar in striking power to 5-6 x 50cal MGs at convergence, but maintaining that efficiency throughout its useful range up to 400 meters. A very nice weapon combination.

By comparison, the MK 108 was a very low velocity weapon (500-540 M/sec), especially for an air-to-air weapon. Good against slower targets with limited maneuverability; not so good against fast and maneuverable targets. MK 108 was certainly very range sensitive.

Muzzle velocity comparison with contemporaneous aircraft guns:

MK 108 ..... 500-540 M/sec
MG 131 ..... 730
MG151/20 ... 790
M2 50cal ... 870

As can be seen, the other weapons listed possess muzzle velocities 35 to 60 pct greater.

p1ngu666
02-21-2006, 11:51 AM
Originally posted by Holtzauge:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by p1ngu666:
rock steady nose cannon in action http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

http://www.tarrif.net/wwii/movies/bf109g_vs_spitfire.wmv

http://forums.ubi.com/images/smilies/59.gif

http://www.tarrif.net/wwii/movies/index.htm

the other ones are stable tho http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Pingu my man, very illuminating! You have just demonstrated what happens when you wave a hose up and down and not hold it steady! Do it all the time in my garden. Totally to the point and very consistant with the point I was trying to make! Muchos gracias!

Seeing your previous posts I know you like to see tests of everything.To convince you about validity, I suggest you perform this test yourself.

Test setup: Drink some coffee, wait for the effects, take a steady grip (if it's not to short), aim and fire. You should now see a steady stream. Wiggle it some to try and align the stream to your target. You should get about the same effect as in the flick. Please post results! Best of luck! </div></BLOCKQUOTE>

alas i dont have a video camera http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif. i do know the effects of coffee, or any liquid intake http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif, but i must confess i dont often drink coffee, very rare.

but i did link to other 109 vids where they was stable. the unstable vid is obivously from a rather excited luftn00b pilot http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Holtzauge
02-21-2006, 01:32 PM
Originally posted by p1ngu666:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Holtzauge:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by p1ngu666:
rock steady nose cannon in action http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

http://www.tarrif.net/wwii/movies/bf109g_vs_spitfire.wmv

http://forums.ubi.com/images/smilies/59.gif

http://www.tarrif.net/wwii/movies/index.htm

the other ones are stable tho http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Pingu my man, very illuminating! You have just demonstrated what happens when you wave a hose up and down and not hold it steady! Do it all the time in my garden. Totally to the point and very consistant with the point I was trying to make! Muchos gracias!

Seeing your previous posts I know you like to see tests of everything.To convince you about validity, I suggest you perform this test yourself.

Test setup: Drink some coffee, wait for the effects, take a steady grip (if it's not to short), aim and fire. You should now see a steady stream. Wiggle it some to try and align the stream to your target. You should get about the same effect as in the flick. Please post results! Best of luck! </div></BLOCKQUOTE>

alas i dont have a video camera http://forums.ubi.com/images/smilies/16x16_smiley-sad.gif. i do know the effects of coffee, or any liquid intake http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif, but i must confess i dont often drink coffee, very rare.

but i did link to other 109 vids where they was stable. the unstable vid is obivously from a rather excited luftn00b pilot http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif </div></BLOCKQUOTE>

Glad to see you have a sense of humor Pingu! Yeah I guess that Me jock was real excited the way he was spraying all over the place. Reminds me of my first date....

Stafroty
02-23-2006, 04:47 AM
does anyone remember the Guncam film where its apparently FW behind B-17, shooting it with cannons, how "much" vibrations there is as he is shooting.

the bomber is flying quite straight on it, and so is FW, just aiming at different parts of the bomber, like gunners, fuselage, engines. it doesnt seem so inaccurate firing to me, even as the fighter is flyin in the turbulence of the bomber.

Stafroty
02-27-2006, 04:55 AM
no one admits to remember?