Jamming

[JDG]

Bob T

I think you are correct - bolt was machined from stock. We measured the bolt heights on mine and a SMG and there was a difference. Using the top of the bolt as a reference point. BG Machine height 1.373" , SMG height 1.366", a difference of 0.007"
Other dimensions were identical- top of the bolt to the bottom of the bolt face that encircles the barrel. We'll see. I am having 0.007" ground off with surface grinder.

[Dan0341]

JDG, is this extra height causing the bolt to rub excessively on the top cover? With top cover in place and recoil spring removed, will the bolt slide back and forth in the receiver when it is tipped forwards and backwards (using gravity to slide the bolt)? If it won't slide with gravity because of the top cover, have you thought about bending the top cover to allow more room? Just some thoughts.

Dan

[Paul556]

Originally posted by Dan0341
JDG, is this extra height causing the bolt to rub excessively on the top cover? With top cover in place and recoil spring removed, will the bolt slide back and forth in the receiver when it is tipped forwards and backwards (using gravity to slide the bolt)? If it won't slide with gravity because of the top cover, have you thought about bending the top cover to allow more room? Just some thoughts.

Dan

Grinding the bolt will most likely be the fix if it slides easy like you described. I did this to my Norinco to get it running and it worked like a champ. The bolt was OK on the Norinco. It was the receiver that was too short. 0.010" off the top of the bolt and no more binding. I tried bending the top cover at first, but it would still drag some. My case is different in that the bolt was cheaper than the receiver and you should always cut the cheapest part. However, with clear proof that the bolt is out of spec I would want to make it right. Happy grinding.