If your rifle won't shoot consistantly, check the mount that holds the bayonet to the barrel. If you haven't already noticed, it is a sleeve that has the front sight on it and the bayonet lug as well. These can get loose from using the bayonet. Mine was shooting all over the place when I first got my M44, then figured out the front sight was moving all over the place. As I only paid $49 for mine, I just welded the sleeve to the barrel. No more problems. Just a couple of quick tack welds with my MIG welder. You gunsmithing types out there may cringe, but like I said, I only paid $49 for the rifle. I did not have much to lose. I've put about 500 rounds through it since then. No problems.
BTW, shawnyboy, I hope seriously you don't mean you have tried .308 Winchester rounds in the 7.62x54R rifles. That is NOT an interchangeable cartridge. A very dangerous situation.