How to add wear to RPG-7 and Bulldog? (STALKER: Clear Sky)

I would like the RPG to completely break down after 5 shots and only after that the weapon jammed. I tried to change some settings in the files, as a result, after the second shot, the RPG jammed, but he managed to make a shot without spending the projectile. In addition, the animation is a bit strange, in some moments a projectile (shot) is visible in the barrel, although it is not there. I didn't even try with a bulldog