The PPS-43 submachine-gun used by the Red Army during the Great Patriotic War has quite a fascinating developmental history.
Less than a month before the beginning of Barbarossa in June 1941, the Red Army had formally adopted the more historically well known PPSh-41 (Shpagin) submachine-gun, having undergone an epiphany regarding the necessity of submachine-guns during the winter war.
The PPSh-41 was chambered for the 7.62 * 25mm Tokarev cartridge. It had an exceptionally high rate of fire (up to 1,000 rounds per minute). The greatest factor negatively impacting on its reliability, and the greatest limiting-factor in its mass-production, was its 71-round drum-magazine.
A more reliable 35-round box-magazine was later developed for the PPSh-41.
All of the larger belligerent-nations in the second world war developed cheap submachine-gun models which could be mass-produced by workers and machine-tools not previously specialized for firearms manufacture. This meant using stamped and welded sheet-metal components rather than building milled receivers.
The United States military largely replaced the Thompson machine-gun (far too expensive) with the M3, better known as the “grease-gun” because it looked a lot like an automotive mechanic’s grease-gun. In total, it cost the US War Department only $19 to buy a grease-gun, about a tenth of the price of a Thompson.
Of course, this required exceptionally good design. A well designed weapon is not necessarily the most technically sophisticated prototype – the most important aspect of good design is that the prototype comes through the process of cheap mass-production to STILL be a reliable weapon. This means that simplicity is almost always a virtue.
At the risk of sounding obvious, quite often, the most technically sophisticated prototypes turn out to be the most unreliable weapons under actual battlefield conditions.
Usually, the fewer moving parts, the better.
In this respect, aside from the problematic drum-magazine, the PPSh-41 was a good design. It required only 13.9 kilograms of raw materials and 7.3 hours of machine-time per gun to build.
The USSR State Defence Committee was not completely happy, however – they wanted something which was even faster and cheaper to build.
This resulted in the development of the PPS-42 by Alexey Sudayev, based on an earlier design by Ivan Bezruchko-Vysotsky.
Like the Shpagin, the PPS was also chambered for the 7.62 * 25 mm Tokarev cartridge. It was built entirely from heavy-gauge sheet-steel.
The PPS-42 first went into production in Leningrad DURING the German siege. In total, the city of Leningrad produced 46,000 PPS submachine-guns during the siege. The PPS-42 models were transported directly from the Sestroretsk Tool Factory for immediate use at the front.
For all practical purposes, it was first tested under actual battlefield-conditions, which helps to explain its rapid technical improvement and the ironing-out of reliability-issues over the following months. This resulted in the PPS-43 designation which went into mass-production across the USSR in early 1943.
While the PPSh-41 (Shpagin) required 13.9 kilograms of raw materials and 7.3 hours of machine-time to build (very impressive efficiency), the PPS-43 required only 6.2 kilograms of raw materials and 2.7 hours of machine-time per gun. These savings enabled the State Defence Committee to build 350,000 more submachine-guns per year. Furthermore, its mechanical workings were even simpler than the Shpagin, which made it exceptionally reliable under battlefield conditions.