In the mid 1950s SFR Yugoslavia sought to replace the M49, its indigenously produced copy of the PPSh-41, with a new submachine gun. The M56 borrowed heavily in terms of ergonomics from the MP40, however, the mechanical similarities are minimal. The M56 does not use the MP40′s telescoping recoil spring. The bolt and receiver were instead copied from the Beretta Modelo 38/44. As such the M56 was a simple blowback weapon, it continued to use the earlier M49′s 7.62x25mm chambering. The M56′s curved box magazine is proprietary and not interchangeable with the M49/PPSh’s 35-round magazine , though similar to the PPS’s magazine. Manufactured by Zastava, the M56 had a long tubular receiver and a plastic moulded lower receiver and pistol grip. After issues with the plastic lower cracking in cold weather a wooden insert inside the lower was added. The M56 copied the MP40′s folding stock and as a result the weapon is quite long, measuring 60cm (23in) with the stock extended. The weapon’s controls were simple with a right side cocking handle, simple magazine catch and a cocking handle safety, which when turned 90 degrees clockwise, locks the bolt in place. The M56 also had a push button fire selector for semi and fully automatic fire. The M56 has a hooded front sight and a 100m & 200m rear leaf sight, the weapon could also be fitted with a bayonet. Zastava began manufacturing a version chambered in 9x19mm, the M65, in 1965. The M56 was issued to the Yugoslav People’s Army and border guards, initially issued at the squad level during the 1950s. The M56 was simple, accurate and reportedly well liked weapon. It was largely replaced by the Zastava M70 AK derivatives and the M84, a licensed copy of the Czechoslovakian Vz.61 Skorpion for vehicle crews.