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Aaron_GT
04-10-2004, 03:42 AM
I was walking to PC World and doing some
thinking to pass the time, and came up with
this possible theory..

I had looked at the information for the XM312
which quotes 1.5 mils of dispersion for one
sigma of a normal distribution. About 75%
of the rounds should hit within 1 sigma.

The WW2 definitions seem to be either 80%
(about 1.3 sigma) or 100% (typically
people consider 3 sigma to be a good
approximation for this).

I am wondering if someone took the 5 mils
dispersion figure for static tests of
the M3 (assuming M2 is similar) and
misunderstood that this was a 3 sigma figure
and scaled it up by 3 again. An easy mistake
to make, given the conflicting definitions
for dispersion.


In either case, though, ideally it should
be modelled as a normal distribution (I think
clint-ruin just noted this in another thread
too). With a uniform spread of rounds, it
might be better to use 1 sigma for dispersion.

It's only a theory!

By the way, 1.5 mils for 1 sigma means the
2000 yard 2 shots in a row hitting the same
target is an incredible piece of luck - if
you do the maths it would happen less than
1 in 25 times you tried it!

Aaron_GT
04-10-2004, 03:42 AM
I was walking to PC World and doing some
thinking to pass the time, and came up with
this possible theory..

I had looked at the information for the XM312
which quotes 1.5 mils of dispersion for one
sigma of a normal distribution. About 75%
of the rounds should hit within 1 sigma.

The WW2 definitions seem to be either 80%
(about 1.3 sigma) or 100% (typically
people consider 3 sigma to be a good
approximation for this).

I am wondering if someone took the 5 mils
dispersion figure for static tests of
the M3 (assuming M2 is similar) and
misunderstood that this was a 3 sigma figure
and scaled it up by 3 again. An easy mistake
to make, given the conflicting definitions
for dispersion.


In either case, though, ideally it should
be modelled as a normal distribution (I think
clint-ruin just noted this in another thread
too). With a uniform spread of rounds, it
might be better to use 1 sigma for dispersion.

It's only a theory!

By the way, 1.5 mils for 1 sigma means the
2000 yard 2 shots in a row hitting the same
target is an incredible piece of luck - if
you do the maths it would happen less than
1 in 25 times you tried it!

VW-IceFire
04-10-2004, 09:30 AM
So in conclusion is this a modeling error made by the team in the same vein as the Revi gunsight thing or something else? http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

http://home.cogeco.ca/~cczerneda/sigs/tmv-sig1.jpg
RCAF 412 Falcon Squadron - "Swift to Avenge"

Aaron_GT
04-10-2004, 09:39 AM
Well, it's only a theory! I was just speculating
that a misreading of the meaning of a dispersion
figure could have easily led to 3 times the
required dispersion being entered.

crazyivan1970
04-10-2004, 10:13 AM
GT, are we going to have another 50 pages on this one....just curious http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

V!
Regards,

http://blitzpigs.com/forum/images/smiles/smokin.gif

VFC*Crazyivan aka VFC*HOST

http://www.rmutt.netfirms.com/coop-ivan.jpg

http://www.rmutt.netfirms.com/vfc/home.htm

Kozhedub: In combat potential, the Yak-3, La-7 and La-9 fighters were indisputably superior to the Bf-109s and Fw-190s. But, as they say, no matter how good the violin may be, much depends on the violinist. I always felt respect for an enemy pilot whose plane I failed to down.

Aaron_GT
04-10-2004, 11:36 AM
Dunno - maybe we can get Tully to kill the
thread if it goes over 25 :-)

Marc-David
04-10-2004, 03:57 PM
Hi to all!

I'm regularly shot down by P51s from 500m or more.
I shoot down P51s from my P51 at 600m.
I can down multiple Hurricanes or other early war birds with CR42. (2x12,7mm)
I've heard&read of German fighters coming home with 100+ 12.7mm wholes in their crates.

AT SimHQ "Scalps" posted the following
Quote from http://www.simhq.com/simhq3/sims/boards/bbs/ultimatebb.php?ubb=get_topic;f=98;t=008957

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>
I recall flying in HL a few months back in a P-47. A couple Jugs were mixing it up with a few 190s. The 190s clearly had the altitude and speed advantage and were scoring kills consistantly. Altitude was 2000-4000m. A few 190s made mistakes and were shot down (poor energy management - not enough attack speed). The sides were a bit even with the edge going to the 190s (Jugs vs. 190s).

I had the convergence in the Jug set at 1000m. I loaded up "extra ammo" and recall a nice vertical zoom climb after an aggressive dive. To my surprise, a 190 was directly above me flying level at 1200m range (1200m directly above me). He thought I was no threat and made no attempt to BnZ me or alter his straight and narrow course. I began firing at 1200m well ahead of him as he was flying towards my line of flight and line of fire, ever closer to 90 degree deflection as I went straight up. I held the trigger down as I closed the gap to 1000m, gaining altitude in the pure vertical passing through 500kph. It was a three second burst and I had lots of lead with my aim. Suddenly, BOOM! He exploaded! I couldn't believe it.

The 8 - 50 cal with convergence set at 1000m compressed the fire to a single "laser beam" - similar to the 1-16 - and blew that 190 out of the sky. I was simply amazed, in shock actually, and learned that 50 cal was very accurate even at distances of up to 1000m. The 190 is one tough and rugged bird but enough rounds penetrated its skin.
<HR></BLOCKQUOTE>

If people can shoot like this with the
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>crappy, porked, undermodeld <HR></BLOCKQUOTE>12.7mm guns, the dispersion/"dispursion" http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif might be one thing, but there might be the gunnery-skill thing, too. Be sure!

Yours, Marc-David

clint-ruin
04-10-2004, 05:10 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Aaron_GT:
Dunno - maybe we can get Tully to kill the
thread if it goes over 25 :-)<HR></BLOCKQUOTE>

I would agree that it would be good to look into the 'typo effect'. Even the most impeccably researched sources and piles of data it doesn't matter if someone's entered 5.1 rather than 1.5 into the FB data file :&gt;

At the very least JTDs chimney tests show that we have a fairly basic model for dispersion - square boxes with the rounds being as likely to impact in the corners as the centre. No curve of distribution at all it seems. That could possibly use some work but I wonder how much work it would be to change..

Marc-David:

Noone is complaining about hitting power. That part of the .50 is as good as anyone could ask for. They are wondering why the .50 cal has practically higher dispersion than the MK108 shot per shot. It is also not good to compare the .50 cal to a "laser like the I-16" when the I-16 also has some of the highest dispersion modelled in FB.

http://users.bigpond.net.au/gwen/fb/leninkoba.jpg

LuftLuver
04-10-2004, 08:28 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by crazyivan1970:
GT, are we going to have another 50 pages on this one....just curious http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

<HR></BLOCKQUOTE>

I would imagine that when we do get 50 more pages, then there must be something to this claim of too much dispersion for the .50 cal.

Eh? http://ubbxforums.ubi.com/images/smiley/16x16_smiley-sad.gif

WWMaxGunz
04-10-2004, 08:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Marc-David:
Hi to all!

I'm regularly shot down by P51s from 500m or more.
I shoot down P51s from my P51 at 600m.
I can down multiple Hurricanes or other early war birds with CR42. (2x12,7mm)
I've heard&read of German fighters coming home with 100+ 12.7mm wholes in their crates.

AT SimHQ "Scalps" posted the following
Quote from http://www.simhq.com/simhq3/sims/boards/bbs/ultimatebb.php?ubb=get_topic;f=98;t=008957

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>
I recall flying in HL a few months back in a P-47. A couple Jugs were mixing it up with a few 190s. The 190s clearly had the altitude and speed advantage and were scoring kills consistantly. Altitude was 2000-4000m. A few 190s made mistakes and were shot down (poor energy management - not enough attack speed). The sides were a bit even with the edge going to the 190s (Jugs vs. 190s).

I had the convergence in the Jug set at 1000m. I loaded up "extra ammo" and recall a nice vertical zoom climb after an aggressive dive. To my surprise, a 190 was directly above me flying level at 1200m range (1200m directly above me). He thought I was no threat and made no attempt to BnZ me or alter his straight and narrow course. I began firing at 1200m well ahead of him as he was flying towards my line of flight and line of fire, ever closer to 90 degree deflection as I went straight up. I held the trigger down as I closed the gap to 1000m, gaining altitude in the pure vertical passing through 500kph. It was a three second burst and I had lots of lead with my aim. Suddenly, BOOM! He exploaded! I couldn't believe it.

The 8 - 50 cal with convergence set at 1000m compressed the fire to a single "laser beam" - similar to the 1-16 - and blew that 190 out of the sky. I was simply amazed, in shock actually, and learned that 50 cal was very accurate even at distances of up to 1000m. The 190 is one tough and rugged bird but enough rounds penetrated its skin.
<HR></BLOCKQUOTE>

If people can shoot like this with the
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>crappy, porked, undermodeld <HR></BLOCKQUOTE>12.7mm guns, the dispersion/"dispursion" http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif might be one thing, but there might be the gunnery-skill thing, too. Be sure!

Yours, Marc-David<HR></BLOCKQUOTE>

Well if you're going to quote events from before the latest change then can I ask if they suit your view given the reference to [crappy, porked, undemodelled]? That's not how it is now.

You'll get hits at range now without having to aim accurately since the shots go all over in a very wide dispersion. Waste enough ammo and you can tear planes apart. From 200m or less it only takes 6 50's a few seconds. If you stop and consider the ammo used and then check number of hits in arcade playback then you might lose some of those subjective snap impressions perhaps about when you realize that things change from patch to patch.

BTW, my 190's, any of them, has ALWAYS made much quicker work of targets using everything as it should be.


Neal

VW-IceFire
04-10-2004, 11:36 PM
Few things happening in that recount.

1) The non-complex DM model of the FW190 in the 1.22 patch a few months back.

2) The different DM globals that allowed all weapons to do more damage.

3) The fact that the shots were being fired up into the belly of the FW190.

4) Lucky hits to a certain part of the DM in that time would have taken a FW190 apart.

Most of these things are different in AEP. Its quite possible to kill things with .50cals...I regularly do...but they aren't exactly the way they should be either and they have suffered just as much as other guns recently. The patch fixes many of these things...hopefully .50 cal dispersion.

http://home.cogeco.ca/~cczerneda/sigs/tmv-sig1.jpg
RCAF 412 Falcon Squadron - "Swift to Avenge"

Vanya
04-12-2004, 05:56 AM
Just to note that the 12.7mm Breda in the CR42 does not fire the same cartridge as the Browning M2 .50cal:

Breda/SAFAT:
12.7mm x 81SR Mass:82g MV:760ms

M2 Browning .50 cal:
12.7mm x 99 Mass:112g MV:890ms