That sounds more like a cartridge that a select fire carbine might use than an automatic rifle circa 1938? I suspect the US Army circa 1938 is going to want a longer effective range and probably better penetration for an automatic rifle than such a cartridge would likely provide. Still it might be a nice round for a carbine. I could also see a select fire carbine (perhaps with a heavier barrel and a bi pod ?) filling a niche short range automatic carbine role. Maybe if the US Army also had a belt fed GPMG, that was suitable for squad level use (or also retained the BAR ?) they might see a role for a short range automatic carbine as a support weapon ?
Yes, it's more like a lower powered intermediate cartridge than a pistol or rifle cartridge. It was just mentioned as a potential option for a SAW like the 9mm SMG since OR showed that infantry combat ranges at the squad level were sub-300 yards in WW2 and Korea (less in Vietnam). In that case more ammo is better, so light weight, less heat producing, and faster is the best combo to achieve hits per the SALVO research program (and more lethal too per the ALCAD research program).
No doubt OTL US Army would want a battle rifle cartridge and a universally compatible one for all roles, but we're in thought experiment territory here.
The GPMG at the squad level was basically judged a bust by Germans and Brits during WW2 and the US during Vietnam. That brought us the StG44, EM-2, and M249 SAW instead.
As to your idea of a select fire carbine, they could have beefed up the M1 Carbine and necked the cartridge down to .22 caliber, though they'd probably want to lengthen the case, as the .22 Spitfire was a tad underpowered because it was such a thin case (a .19-20 cal version would be better suited to the case size), which restricted the powder capacity when necked down.
Here was an OTL effort to upgrade the M1 Carbine, no reason they couldn't have made a .22 version, though a .20 version would be a better match for the size of the case and powder load:
Having experience with the drums on the M1928, winding the drum isn't a problem, Finns and Russians had no issues with that, or the rounds rattle in the drum
You sure about that? The Soviets dumped the drum on the PPSH41 later in the war over reliability issues and the PPS43 only ran on stick mags.
But like the PPSh, Drums must be matched to the weapon, or they won't be reliable. Jam city.
But the main reason?
100 round drums, loaded, are Heavy
100 rounds of 45Auto is almost 5 pounds by themselves. How many of those rascals you expecting guys to hump around all day long, stored in a big steel can?
It's one thing to have some loaded while you're doing a drive-by shooting on another Family's Mooks in a V8 Ford, but dont forget the Tommy gun is around 10 pounds unloaded. it's a heavy beast to walk around with
That's a pretty good reason too.
Why, what is a Automatic Rifle if not an early heavy battle rifle or a early undeveloped lacking LMG......?
Open bolt heavy magazine fed weapon capable of greater sustained automatic (well burst at least) fire than even a heavy barreled rifle.
It would be a SAW rather than an LMG largely thanks to lack of a quick change barrel and the need for a 2nd crew member to operate at full capacity, while generally being lighter. The BAR failed in that by WW2, as the Bren was nearly as light as it, but basically an LMG.
The problem is with hindsight its easy to drop the weight/cost or give it a high rate of sustained fire (better feeding or QC barrel) and both are almost certainly better but stop it being an Automatic Rifle?
Yes, but adding more complexity in the feed system or by having a QC barrel increases weight and complexity in manufacture and operation. Certainly it improves certain categories of operation in the field, but at a cost, which generally includes increased weight, things that could go wrong, and cost, and manufacturing time and resources.
The problem is the technology (apart from stamping?) isnt really hard to do they probably could have built mini14s if they have the design easily?
Given what a nightmare it was to get the M14 to work apparently it wasn't as easy as you think to get that going. Even the FAL/FN-49/SLEM-1 took years to get working despite being started pre-WW2.
Since the US didn't use stampings in small arms in WW2 apparently it wasn't a move that thought was viable at the time, though the Germans did prove them wrong in that regard.
We'd need some serious changes in US small arms construction/design conceptions to go there.
Technically something like the FAMAS was viable at the time too, as John Pedersen invented that operating system and it was already used in Europe to some degree, but they never opted to try that out.
That is what I am alluding to yes
I was looking at a COTS solution but the Lanchester SMG used 50 round mags to the side with out issue as far as I am aware - and if firing from the Bipod then it should not pose any stability issues (if any!)
Sounds like we might have a decent option there even with the sight picture disrupted by the magazine and it sticking up so high.
So out of a pistol 7.62 x 25 Takarov depending on ammo and weapon has a MV of between 1200-1800 FPS
A hot loading (more powerful propellant) out of a longer Barrel (325 mm for the ZK 383) should result in superior MV (I am guessing 2000-2200 MV?) and increased effective range.
A spitzer type round might also improve range characteristics?
Not sure how much hotter you could make it without getting into PETN supplemented powder like in the German 'verbessert' loads for aircraft MGs (which required special high pressure tolerant MGs and heated up more quickly). If you do that though then you need at least a delayed blowback system or a gas piston, because the pressure will be too high to use in a simple blowback system without a really heavy bolt (too heavy to be practical) and/or a very strong spring. I have been wondering if a MP40 style telescoping bolt with a stronger spring might be enough though to deal with the increased pressure...
I highly doubt though that you'd be able to improve the muzzle velocity that much given the small powder capacity of the 25mm long case even with a 20 inch barrel (at some point barrel length stops increasing muzzle velocity and friction starts slowing down the bullet), though to LAD did increase the Tokarev's velocity somewhat over the PPSH41, I just cannot find what the number was.
The Spitzer would help, but the increased weight due to the larger internal volume of the bullet might offset whatever gains would come from increased barrel length, which heavier bullets would increase pressure. See the .30 carbine high pressure load as an example; the standard bullet was the 110 grain round nose, but the high pressure load was a 150 grain spitzer bullet:
Does anyone have a picture of an actual M1 Carbine - M18 High Pressure Test round that they could post. Also, can anyone give any headstamp data on the test rounds?
forum.cartridgecollectors.org
You could 'cheat' though and either fill the bullet with steel instead of lead or just go with a solid steel bullet coated with copper, which would cut weight by about 25% for the overall bullet (steel is about 30% lighter than lead, but only the core is lead).
Using the 7.92mm flat base spitzer as a model, the bullet weighed 154 grains total, the lead core was about 120 grain and the gilding metal jacket was about 34 grains (a 7.62 should be slightly less for both).
So replacing the lead in the .30 carbine 150 grain bullet would probably save about 36 grain, which gives you a heavier bullet than the 110 round nose, but not by much probably 114-115 grains total. Keep in mind though the 7.62x25mm bullet for the Tokarev was only about 77 grain.
I will say I am bit skeptical about using pistol based cartridges at longer ranges in wind based on some time spent observing relatively hot 9x19 mm rounds hitting target back stops some distance from the targets at an outdoor range in high wind, but I suppose a well engineered solution could address this.
