Machine-guns

[Mark IV]

A refugee from the Great HE Skip-Fire Debate, this topic is only to point out that there were substantive performance differences between the MG34 and the MG42 which MAY someday merit modeling.

The MG34 certainly cost more to build, not only in material, but in labor. The tight fit of the parts was the result of high tolerance machining which took longer to produce, had a higher scrap rate, and was less dirt tolerant.

MG42 was designed to lower production costs and to improve an existing design. One means of accomplishing both ends was to engineer a certain amount of "slop" into the tolerances- not only could they be machined faster, but they were less susceptible to jamming due to dirt and powder fouling.

Reduced bearing surfaces also increase equipment life and help increase rate of fire. The slop in the action had no direct effect on accuracy. Since the MG42 fired from the closed bolt position (delayed blowback), first-round accuracy "should have been" slightly higher (though it was considered somewhat less accurate for burst fire than MG34, from a bipod, due to higher vibration).

There is a big difference between 850 rpm and 1200+ rpm (with a lighter bolt-head, the MG42 could get to 1800 rpm), particularly if you are downrange. There is an even bigger difference between a jammed weapon and a firing one, and I don't know if MTBF data is available for the two, but an educated guess might suffice.

The difference was compared to the change from P08 to P38, though I wouldn't consider that fully analogous (and I would definitely draw the line at modeling different pistols!). MG42 was an evolutionary design, where P38 was a revolutionary design. Luger P08 did have beautiful fit and finish which worked to its disadvantage in fouling situations, and an almost kinky mechanical principle. The P38 was a radically different and superior mechanical concept altogether.

MG42 was also designed to be fully operated and serviced with mittens on- nice for those chilly Russian mornings.

[Username]

yeah but the P08 looks cooler.

I think the center rocking fire selection trigger on the MG34, while maybe an overcomplication, was just plain freaking cool too. Imagine quickly squeezing off single rounds till a tracer flys out where you need em and then going full auto. I think it would be a great feature on an assault rifle.

BTW the rate of fire of a machine gun does not effect its accuracy. I remember reading american marines modifying water cooled 30 cals to achieve over 1000 rounds per minute. The author claimed that as long as the weight of the weapon was sufficient, high rates of fire actually acted to smooth out the weapon. Like higher RPMs on an engine. The marines modified the weapons by removing mass from the bolt. Just drilled out bigger and bigger chunks. Maybe the germans should have had an optional lead chunk to put in MG42s when firing from the bipod.

Lewis

[Fenris]

You also may want to be wearing a mitten when changing the barrel after putting a couple of thousand rounds thru it.

Fen

Man I can't wait to play this thing!

[Mark IV]

At full auto, they were supposed to change the barrel every 250 rounds. The change took 5-6 seconds.

How could almost doubling the ROF not affect the accuracy of bursts? Almost every article on the MG42 comments on this. Recoil causes muzzle jump and shooter vibration, and even the short recoil design has a mass of spring-buffered steel slamming back and forth nearly 25 times a second.

P08 does indeed look cooler. Unfortunately, body styling wasn't much of an advantage in tactical emergencies. I own one of each (Erfurt 1918 Luger and a Mauser-built '42 P38) and there's no comparison- the P38 shoots rings around the Luger, is far easier to service, and has the handy and safe double-action. To be fair, my Belgian occupation Nazi-proofed Browning Hi-Power outshoots them both, and is far more tolerant of different ammunition types.

[Guest R Cunningham]

I have read of a compensator device that modifies the ROF to match the "natural frequency" of the weapon. Supposedly this allows submachineguns to be fired comfortably with the weapon rocking lightly in the hands. On some guns it was supposed to increase ROF while others required reductions.

Also the G11 rifle had a high enough ROF to allow it to fire a three-round burst before the firer felt the recoil. To me that sounds like it would enhance accuracy.

[Guest aaronb]

<BLOCKQUOTE>quote:</font><HR>Originally posted by R Cunningham:

I have read of a compensator device that modifies the ROF to match the "natural frequency" of the weapon.<HR></BLOCKQUOTE>

It takes a certain amount of time for a firearm to 'return to battery', i.e., to return to its original firing position. That's the 'natural frequency'. Depends on the weight of the gun, the power of the cartridge, the firing mechanism (short, long, blowback, etc.) the mounting system (tripod, bipod, sling, etc.), and how the user holds it - firmly, limply, etc. Some people hold shoulder-fired full-auto firearms poorly, and they never do return to battery, just keep recoiling up and to the right in a big, dangerous arc.

So, if you hit a sweet spot where the next round fires just as the gun system is back to where it started, you have great accuracy. A skilled operator can affect this with proper grip.

<BLOCKQUOTE>quote:</font><HR>Also the G11 rifle had a high enough ROF to allow it to fire a three-round burst before the firer felt the recoil. To me that sounds like it would enhance accuracy.<HR></BLOCKQUOTE>

Yep, for a three-round burst. Run it at full-auto at that ROF (if you could, but the gun won't let you), and you'll be on your ass firing at birds in no time. I suppose with a heavy tripod you could do it until the barrel melted or the ammo ran "Low".

As for Mark IV's points, it seems that modelling ROF (FirePower), reliability (JAM likelyhood), and cost (points in a DIY scenario) would be worthwhile - in CM2.

Easy for us to say; we're not the guys writing the extra code. If they were rare in the late war, it would be easier to just leave them out - rare tanks are cool, rare MG systems just don't have the same ring to me. YMMV.

[Mark IV]

Neither MG 34 nor MG 42 was rare in the late war, though I suspect that's not what you meant (presumably you mean the oddball variants like MG15).

And rare AFVs are certainly more interesting. Wehrmacht formations using captured T34s would be a real hoot, whereas a scenario featuring captured MGs is not quite as stirring...

[Guest R Cunningham]

Actually I was referring to the natural weapon harmonics and not the actual rate that a gun will fire at given its feed system and method of operation. This regulator is used to adjust the "natural" ROF (usually downward) so that the forces acting upon the weapon cancel each other out as much as possible.

The example referred to in my reference is the 9mm Bushman PDW, a small one-hand SMG not unlike the Czech Skorpion etc. without the regulator its natural ROF is 1400 RPM and it is uncontrollable. "but with the regulator installed it fires at 450 RPM and rocks gently in the hand, delivering all its shots into the same area of the target with no rise or deviation at all." (from Military Small Arms - 300 Years of Soldiers' Firearms by Hogg and Smith)

[Username]

Weight of weapon and mount is also a big factor. So in the case of MG34 and MG42 being roughly the same weight but one firing faster than the other translate into more vibration. If more weight in the form of a tripod and sandbagged legs on the platform are added then the vibrations are damped.

If the germans had a 3-shot option on the MG42 (in addition to full auto) it would have been alot more successful. The M16a2 that the US uses nowadays has NO full auto but a 3 shot and 1 shot option. The 3 shot happens ALOT faster than the full auto M16s I was used to. This reduces muzzle rise losses and actually saves ammo.

Lewis

[spider]

you can fire full auto on the original version of the g11, held tightly a 4/5 rnd burst can be achieved before it reaches for the stars, of course its hard enough to just tap out 10 rnds with a weapon like that,,

there was a proposal to make a hmg with a scaled up caseless round but when the germans didnt buy into the g11 i dont think it went ahead...

[Mark IV]

The MG42 accuracy issue was only associated with bipod use. As an HMG it had all the stability of the '34.

Burst fire is cool, but a relatively recent innovation, as far as I know. And of course muzzle climb is less of a factor with 5.56 than with 7.92mm.

Last I checked on caseless there were still some corrosion problems that put front-line projects on hold. I am eager for affordable caseless to filter down to my lowly sportsman's level.

[Guest aaronb]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Mark IV:

The MG42 accuracy issue was only associated with bipod use. As an HMG it had all the stability of the '34.

[...]

I am eager for affordable caseless to filter down to my lowly sportsman's level.<HR></BLOCKQUOTE>

That's entirely sensible, as the tripod would mechanically limit dispersion.

As for caseless ammo for private use, the RCMP (Canadian federal police) has already stated that they would lobby to have it banned, as criminal science uses marks on cases left at crime scenes to match a gun to a shooting. And in Canada, banning such things takes just a stroke of the pen through the 'Order In Council' mechanism. No debate. The US has the 'Executive Order' mechanism, and I suppose other countries have similar mechanisms.

So, don't hold your breath for caseless in your hunting rifle. Hold your breath, instead, for the Gold Demo.

[Mark IV]

The Austrian Voere (sp?) hunting rifle was already offered for sale in the US using caseless ammo. It was reviewed by Finn Aagard a couple of years ago.

No comment on the Executive Orders... that subject's been done enough here.

I did find that the MG42 could be modified in the field to accept the ammo box for the MG34. That would also increase the cyclic rate!