Afanasev A-12.7
| A-12.7 aircraft machine gun | |
|---|---|
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| Type | Single-barrel aircraft machine gun |
| Place of origin | Soviet Union |
| Service history | |
| Used by | Soviet Union, Russia |
| Production history | |
| Designer | Nikolay M. Afanasev |
| Designed | 1949–1953 |
| Manufacturer | Tulamashzavod Tula Izhmash Izhevsk Kovrov KMZ |
| Produced | 1953–1983 |
| Specifications | |
| Weight | 25.5 kg |
| Length | 1,423 mm |
| Barrel length | 1,005 mm |
| Width | 153mm |
| Height | 154.5 mm |
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| Cartridge | 12.7x108 Soviet |
| Caliber | 12.7 mm (0.50 in) |
| Barrels | 1 |
| Action | Gas operation |
| Rate of fire | 800–1,100 rpm |
| Muzzle velocity | 818 m/s |
The Afanasev A-12.7 is a heavy machine gun developed by Nikolay M. Afanasev in 1949 and adopted for service in 1953. This gun was supposed to have a considerably higher rate of fire than its predecessor—the Berezin UB aircraft machine gun. Due to excessive barrel wear however, it was eventually limited by an electrical trigger to a rate comparable to the Berezin UB. Initially intended to be mounted in the defensive turrets of the Tu-4 bomber, the A-12.7 was ultimately installed only in trainer aircraft and helicopters. Nevertheless, it was produced for 30 years.
After the Second World War various attempts were made to increase the rate of fire of the Berezin machine gun. Reducing the cycle time by increasing the speed of the moving parts was the most obvious thing to do. However, this resulted in a considerable reduction of life and reliability. Another attempt was to reduce the motion length of the moving parts while retaining their speed within permissible limits. N. M. Afanasev took a different approach by introducing an acceleration lever, which transferred the energy of a short motion actuating slide into a long motion of a chambering and case extraction arm. This way the motion length of the actuating slide could remain shorter than the overall length of the cartridge, thus increasing the rate of fire. Later, the same operating mechanism was used in the 23mm AM-23 and ZSU-23 cannon as well.
Afanasev's prototype 12.7mm machine gun was designated TKB-481 and reached an impressive rate of fire of 1,400 rounds per minute. However, because of barrel wear problems a special electrical trigger system was introduced, that artificially reduced the rate of fire to 800 - 1,100 rounds per minute. With this modification the barrel life increased to 4,000 rounds, however the gun no longer had any distinct advantages over the Berezin UB. Nevertheless, in the autumn of 1953, Afanasev's 12.7mm aircraft machine gun was adopted put into production under the designation A-12.7. The GRAU index of the weapon is 9-A-016P.
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