"Conclusions on the proving ground trials of 7.62 mm automatic rifles, converted from semi-automatic rifles, with 10-15 round magazines showed that:
- Groups at 100 meters when firing in bursts increase by 3-3.5 times.At 300 meters, only 25-30% of the bullets strike a 3x3 meter target.At 500 meters, up to 30% of the bullets strike a 3.5-4 meter target.While shooting with a 15 round magazine, grouping gets worse, and it is difficult to fire while prone due to the protruding magazine.
- When shooting at targets, only the first bullet hits.
- The ability to aim is limited to 50 shots over the span of one minute. After that, the barrel overheats, and a mirage effect is achieved, which impedes aiming.
- The automatic rifle jams:
- With thick grease: 2-4% of the time
- With dry parts: 12-14%
- In dusty conditions: 14-50%
- While aiming up or down: 8-12%
- The barrel life is 6000 rounds when firing 50 rounds per minute, after which the rifle was allowed to cool. Continuous fire brings the life down to 150-200 rounds.
As a result of trials, it was concluded that:
- Is is not viable to create an automatic rifle from a semi-automatic one by modifying the trigger group.
- It is only possible to aim with such an automatic rifle when using a thickened barrel and lightened bipod.
- When converting a semi-automatic rifle to fully automatic by only modifying the trigger group, its combat usefulness decreases to less than that of a submachinegun.
Conclusions
- Due to the decreased combat usefulness, conversion of a semi-automatic rifle to a fully automatic one is not rational.
- In order to reach required density of fire with a high probability of hitting the target, it is better to use submachineguns, which have the advantages of simpler production, higher reliability, compactness, high magazine capacity, larger stocks of ammunition, etc."