Tuesday 12 September 2017

Lend Lease Impressions: Submachineguns

"11.43 mm Thompson submachinegun M.1928

11.43 mm Thompson submachinegun 

The submachinegun has two types of magazines: 20 round box magazine and 50 round drum magazine.

Significant drawbacks of the Thompson submachinegun include its weight (4.88 kg without a magazine and 7.12 kg with a 50 round magazine) and sensitivity to low temperatures. The 11.43 mm caliber is also high, which limits the amount of ammunition that can be carried (an 11.43 mm round is almost twice as heavy as a domestic submachinegun round).

The following is a comparison of main data of the American Thompson, Reising, German mod. 38 and 40, and our 7.62 mm mod. 1941 submachinegun.

Characteristics
American Thompson submachinegun
American Reising submachinegun
German mod. 38 and 40 submachinegun
7.62 mm mod. 1941 submachinegun
Caliber, mm
11.43
11.43
9
7.62
Length, mm
856
910
835/623*
842
Mass without a magazine, kg
4.88
2.95
3.74
3.5
Magazine capacity
20 or 50
20
32
71
Mass with ammunition, kg
7.12
3.55
4.4
5.4
Maximum range, m
550
274
200
200
Rate of fire, RPM
600
500
400
1000-1100
*Stock extended/stock folded

11.43 Reising submachinegun

11.43 mm Reising submachinegun

Proving grounds trials showed a number of drawbacks, specifically:
  1. Low reliability of various parts (striker, spring, backplate guiding rod).
  2. The magazine is sensitive to dirt.
  3. It is difficult to disassemble.
  4. No spare parts are included.
A significant drawback of the Reising submachinegun is the large caliber, which limits the amount of ammunition carried and makes reloading uncomfortable.

Thompson and Reising submachineguns, supplied by America, are inferior to the domestic and the German submachineguns in maneuver and usage qualities.

To reduce the difficulty of supplying the military with ammunition, and, considering the poor qualities of American submachineguns, the latter will not be issued to the Active Army, and will only be given to rear and auxiliary units. Submachineguns that arrive through Murmansk and Baku will be turned over to the Fronts, as it is difficult to transport them out of there.

Top: M1911 round. Bottom: tracer M1.

11.43 mm pistol rounds had the following issues during trials:
  • Misfire: 6.1%
  • Jammed casing: 2.6%
  • Escaping gases: 0.6%
  • Tough extraction: 0.3%
  • Bullet stuck in gun barrel: 0.2%
An inspection of the exterior of the rounds showed a large number of protruding or sunken primers, as well as looseness. It is also established that the rounds did not come from one batch or one company, but from various years of production (as early as 1934) and companies (4 different companies)."

NKID Political Archive 6-5-348

The ammunition shipped to the USSR with these submachineguns definitely would have soured anyone's first impression.


""ArtKom GAU #12132, Secret

On March 31st, 1942, the shooting range at military base #36 conducted a test of American 11.43 mm pistol rounds, after receiving 3 million such rounds from Murmansk. The tests were conducted by the Senior Assistant of the Chief of the 5th Department of ArtKom GAU KA military engineer 2nd grade Ohotnikov N.S. and Assistant of the Chief of the 5th Department of ArtKom GAU KA military engineer 2nd grade Karagodin G.K., following the program outlined in this document.

The purpose of the tests was to establish the condition of the received rounds. Rounds were taken from 10 crates, 100 rounds each. The results were as follows:

1. External inspection of the rounds

300 rounds were visually inspected. The inspection shows that the rounds have scum on the casings, and dirt in the casing base. Some rounds have a stamp, some do not. Most rounds have primers sticking out, but some have primers sunk in very deeply. 

The bullets are red brass, the casings are yellow brass, but five rounds (1.7%) had a red metallic casing (probably red brass). Most of the cartridges are produced by Remington (with a stamp on the case "REM-UMC.45ACP), but there are others:
  • Western: 6 (2%)
  • WRA Co: 4 (1.4%)
  • FA-34: 2 (0.7%)
  • FA-40: 6 (2%)
  • RA-41: 2 (0.7%)
During visual inspection, the following defects were found:
  • Dented primer: 6 (2%)
  • Ragged primer edges: 40 (13.3%)
  • Impacted primer: 46 (15.3%)
  • Crooked primer: 10 (3.3%)
  • Weakly housed bullet, removable by hand: 1 (0.3%)
  • Total: 103 (34.4%)
II: Testing by firing from a submachinegun

The rounds were fired from a Reising SMG #5073 and Thompson SMG #S-152550. 970 rounds were fired. The following defects were found:
  • Escaping gases (casing ruptured): 6 (0.6%)
  • Tough extraction of the casing: 3 (0.3%)
  • The bullet remains in the barrel (no gunpowder): 2 (0.2%)
  • Misfire (Reising): 59 (6.1%)
  • Misfire (Thompson): 4 (0.4%)
  • Casing stuck on extraction (Reising): 25 (2.6%)
Rounds that failed to fire in the Reising could be fired from the Thompson.

III: Inspection of casings

After firing, 300 casings were examined. The following defects were discovered:
  • Ruptures around primer: 16 (6%)
  • Penetrated primer: 6 (2%)
  • Primer fell out: 2 (0.7%)
Conclusions
  1. 11.43 mm rounds that arrived at Murmansk were produced by various companies, and in various years.
  2. Many rounds have defects, mainly of the primer, which results in escaping gases, rupture of the casing, misfires, poor extraction, and other anomalies.
  3. The received shipment of rounds can only be used after removing 100% of defective items, and even that will not stop escaping gases and bullets getting stuck in the barrel.
"

Via Andrei Ulanov

4 comments:

  1. The Reising was used in combat only briefly by US forces on Guadalcanal. The joke was that the only Japanese ever hurt by a reising were those who got hit when a Marine or Solider threw them away.

    The Thompson always got high marks though.

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    Replies
    1. Not like they had a lot of alternatives before the "Grease Gun" came around anyway, but even the simplified military-standard variants of the Thompson had the usual pros and cons of interwar SMG designs - excellent workmanship but heavy and manifestly ill suited for fast and cheap mass production (ie. not enough of the things to go around).

      There's a reason the major wartime designs opted for "cheap and nasty" instead, taken to something of a logical conclusion with the Sten Mark II...

      That ammo-weight point the document raises is certainly hard to dispute; quick search says the 7.62 mm Tokarev round has a bit over a THIRD of the .45's mass, give or take. That kind of disparity tells when combat troops get loaded down with hundreds of the damn things - nevermind now that the high-velocity Tokarev round has much milder recoil, flatter trajectory and in the Soviet context was sourced domestically.

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    2. Yeah, agreed on the ammo weight. I recall the 5.56mm ammo weighed about half of the 7.62mm ammo it replaced, if memory serves. It's not hard to hump 1,000 rounds of 5.56mm.

      I think the sten gun took the 'cheap' principle just a little too far ;)

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    3. Only the examples that had *actual* manufacturing defects; design-wise the Mk II was about as minimalist as an SMG can get but entirely serviceable - and as it happened so simple to build assorted resistance groups could make their own in literal basement workshops. (Imitation being the sincerest form of flattery, even the Germans got in on the act to help equip the Volkssturm in the late stages of the war...)

      That said once the situation allowed the Brits started making somewhat less austere versions for their own troops. Nothing wrong with better ergonomics after all.

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