Originally Posted by Chas1
Just saw this post. I had a similar problem with my SKS. No rattle. I disassembled the bolt (easy to do) and removed the pin. I soaked everything in brake cleaner for an hour and then used an air compressor to blow dry everything.
The bolt is caked in cosmoline and even though I cleaned the cosmoline I didn't get the bolt good enough. It runs great now and no slam fires even slamming the bolt closed to chamber the 1st round.
The odd thing is that the accuracy feel off a little. I know SKS's aren't known for great accuracy but this one is (was) very accurate out to 120 yards. It's still good for an SKS but not as consistent as my AR's
Good Luck and very fun range rifles !!!
The OP said he had cleaned the rifle, but then found the retaining pin head to come loose and bind the firing pin. That's a problem different from yours.
I can't see how the accuracy can be impaired by a cleaner bolt. Not to dispute the fact, but the problem is likely outside the bolt carrier.