PDA

View Full Version : ShKAS ROF: Don't believe it but, can't prove it



XyZspineZyX
09-03-2003, 07:07 PM
I've been looking for rate of fire info on the ShKAS for a while now. The most common ROF listed is a remarkable 1800rpm. Maybe this was possible in a wing mount, but, I find it hard to believe that it could be achieved in a synchronized mount. Has anyone seen any data on the ShKAS synchronized (firing through the propeller) rate of fire.

The green lasers just seem way too good, but, maybe they were???

Thanks for any help,

faust

XyZspineZyX
09-03-2003, 07:07 PM
I've been looking for rate of fire info on the ShKAS for a while now. The most common ROF listed is a remarkable 1800rpm. Maybe this was possible in a wing mount, but, I find it hard to believe that it could be achieved in a synchronized mount. Has anyone seen any data on the ShKAS synchronized (firing through the propeller) rate of fire.

The green lasers just seem way too good, but, maybe they were???

Thanks for any help,

faust

XyZspineZyX
09-03-2003, 07:24 PM
http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fgun-no.html

This site has good info, but it looks like the ShKAS listed there have the 1800rpm, too.

This is quoted from the link:

"The Russian ShKAS had a high rate of fire and a high muzzle velocity, and was the best of the RCMGs found in fixed installations. The powerful ammunition carried special marks, to prevent its accidental use in rifles. There was also an upgraded model, the Ultra ShKAS, which had an extremely high rate of fire for its time: 2700 rpm. But this weapon seems to have seen no or very limited use, because Russian fighters were quick to adopt medium-calibre machineguns and cannon."

Pretty informative site with great comparison tables, if you haven't seen it already.

_______________________________________
çk?¯kT 2003**

XyZspineZyX
09-03-2003, 07:44 PM
Thanks for the reply SlickStick. I have seen that site. They list a flat 1800rpm but, do not state if this is synchronized or not.

I also wonder if a gun with this high a ROF would have been prone to overheating and jamming? I guess I am used to tank weapon discussion where Soviet weapons are known for inferior tempering and short life spans.

XyZspineZyX
09-03-2003, 07:49 PM
The question about synchronised seems a bit strange to me. Sychronised, ROF is related to the prop rpm., so it can varie dramically.



"Kimura, tu as une tªte carrée comme un sale boche!"

EJGr.Ost Kimura

http://www.jagdgruppe-ost.de/image/ejgrost.gif

XyZspineZyX
09-03-2003, 08:43 PM
KIMURA wrote:
- The question about synchronised seems a bit strange
- to me. Sychronised, ROF is related to the prop rpm.,
- so it can varie dramically.
-

Exactly! But, in FB they don't.

XyZspineZyX
09-03-2003, 09:16 PM
I have an article at home offf the net(by Williams I think) called the "Great Fighter Gun Debate" and I also have the book Rapid Fire. Synchronization does slow the rate of fire. If my memory is correct, I think the typical decline in rate of fire might be 20%,

There is a new book available by Williams and another author called "The Flying Gun" and I have a copy ordered from Amazon. It is already available in GB.

If you read Williams, he doesn't claim that the Soviet weapons were as well made as U.S. or German. In fact, he points out that they were designed for a much shorter service life. Perhaps 2,000 rounds instead of 10,000 or 50,000.

Although I have fired rcmg (M-60's) and the Browning .50 (just a couple of times) I have no idea of their designed service life.

I know that modern pistols (e.g., a Glock or a Sig Sauer) are frequently reported to fire up to 50,000 rounds without any problems (of couse there will be some stopages).

However, the chamber pressure of the a 9mm or .45 APC is probably 10,000 psi (I am relying on memory again) but in a rifle cartridge it is more like 30,000 to 50,000 psi if my memory is at all correct. I don't know what it would be for a .50 or a 20mm but probably pretty great.

I have no experience with Soviet automatic weapons except for their light rcmg (RPD?) and with AK-47s. They certainly have a reputation for reliability under combat conditions. Some of the AKs I have handled were very nicely made in Eastern Europe. The ChiCom rifles were not as well built

My point is that while I think the Browning .50 is undermodeled, my reading of Rapid Fire has lead me to conclude that the Soviet mgs and cannon were very efficent.

Like their planes and their tanks, the Soviets depended upon quality and not quantity. Although in some cases their materials were better than the Germans.

Also, I don't think there is much doubt that the Germans generally had better small arms than the U.S. with the exception of the M-1 Garand vs. their standard Mauser bolt action rifle (can't remember the model).

Also, the Sherman was a generally inferior tank but eventually it got the job done. I recently read part of a text on the failure of the design of U.S. armor in WW2. Some of these problems are on going -- the adoption of the M-16 was somewhat of a scandal. Also, I used to have an article (I teach statistics) comparing the co-axil (sp) gun adopted by the Marine Corp for use on the M-60 tank. A Belgium design did much better (something like a mean of 500 rounds between failures vs. 1200) but the Marines adopted the U.S. designed weapon.

Anyway, this is a complicated subject. And as we used to say, "if it is from Matel its swell."

XyZspineZyX
09-03-2003, 09:29 PM
GMichaelP wrote:
- -
- -
- However, the chamber pressure of the a 9mm or .45
- APC is probably 10,000 psi (I am relying on memory
- again) but in a rifle cartridge it is more like
- 30,000 to 50,000 psi if my memory is at all correct.
- I don't know what it would be for a .50 or a 20mm
- but probably pretty great.
-



A little off... 9mm pressures tend to hover in the vicinity of 30,000 psi while 45 ACP is generally near 17,000 psi. Loads differ of course.

XyZspineZyX
09-03-2003, 09:38 PM
GMichaelP wrote:
- Like their planes and their tanks, the Soviets
- depended upon quality and not quantity. Although in
- some cases their materials were better than the
- Germans.

Don't you mean Quantity and not Quality?

- Also, I don't think there is much doubt that the
- Germans generally had better small arms than the
- U.S. with the exception of the M-1 Garand vs. their
- standard Mauser bolt action rifle (can't remember
- the model).

No - I would disagree, the two armies were equally well equipped design-wise, the only real area in which the Germans exceelled in was with the MG42, which the Allied armies quickly knew to fear, but as you said, the M1 Garand was a very effective piece of kit, and is deservingly known as "The rifle that won the war" (The German Mauser model was the Karbiner98, and later the G43 was used as a sniper rifle and among some of the SS)

Also, it is worth noting that America rushed their arms production - they were not fully prepared for war when it was declared on them, as opposed to Germany who had been slowly building up an army since Hitler came to power.




Message Edited on 09/03/0308:39PM by SS-Sorce

XyZspineZyX
09-03-2003, 09:47 PM
As I said "based on memory." By the way, do you know the chamber pressure for a .50?

Also the rpm will not affect the rate of fire. If the RPM increases by a factor of 10, then each time the prop blade is in front of the muzzle it will be for 1/10th of the time. Faster RPM means more complications in synchronization but in WWII it was done (I think) most of the time using electrical primers. Earlier, interrupter gears were used and of course in WWI it took the French and Brit's about 3 years to develop a decent system. Fokker sold his planes to the Germans because he had synchronization not because his (first) planes were the best.

I used to shoot quite a bit but I live where it is flat. I dropped my membership in the local range and the in door range closed so I almost never get to shoot anything other than the odd squirrel out my bedroom window. I will pop them with a BB pistol when they are on my bird feeder. So a lot of things I used to know about chamber pressures and things I have forgotten.

XyZspineZyX
09-03-2003, 10:07 PM
I have seen the figure of 55,000 psi for some .50 BMG rounds. Don't know if they are all at that level or not.

XyZspineZyX
09-03-2003, 10:45 PM
GMichaelP wrote:
- I have an article at home offf the net(by Williams I
- think) called the "Great Fighter Gun Debate" and I
- also have the book Rapid Fire. Synchronization does
- slow the rate of fire. If my memory is correct, I
- think the typical decline in rate of fire might be
- 20%,
-
-

WIlliams notes 'The effects of synchronisation on other guns varied considerably; for German weapons, which used an efficient electrical system, the reduction in RoF was around 10%. For other (including Soviet mechanical synchronisation) systems it typically varied between 20 and 40%.' http://www.quarry.nildram.co.uk/WW2guneffect.htm

XyZspineZyX
09-03-2003, 10:53 PM
Nice find Bastables! So, if the 40% range is correct, this would put the synchronized ShKAS on par with the Mg17.

XyZspineZyX
09-04-2003, 12:26 AM
germans used electrical syncronization which didnt reduce ROF as the russian counterpart, russians used mechanical syncronization which redused much more ROF.

XyZspineZyX
09-04-2003, 12:40 AM
Synch rate of fire of the ShKas was 1500rpm.
Note that the 1800rpm apply only to the early version of the ShKas (KM-33, KM-35), with the introduction of the KM-36 in 1936/1937 (flex/synch) cyclic RoF was increased to 2000rpm.

Butch

XyZspineZyX
09-04-2003, 01:17 AM
SS-Sorce wrote:
- No - I would disagree, the two armies were equally
- well equipped design-wise, the only real area in
- which the Germans exceelled in was with the MG42,
- which the Allied armies quickly knew to fear, but as
- you said, the M1 Garand was a very effective piece
- of kit, and is deservingly known as "The rifle that
- won the war" (The German Mauser model was the
- Karbiner98, and later the G43 was used as a sniper
- rifle and among some of the SS)

You're right about the Mg42 as it's system was used to base the M60 on, and the Mg42 is still used nowadays (slightly modified) in the form of the MG3.

However I do think the germans were very much advanced compared to the US, especially with the Stg43/44 and the FG42; which were IMO excellent pieces of equipment compared to what the allies could provide (ie no real assault rifle).

I agree the garand was great though, not comparable with the Kar98.

Nic

http://www.randomhouse.com/kids/art/authorphoto/cookie.jpg