What he said. If it is shooting well, velocity is what it is supposed to be and the bolt is NOT coming back I would not worry about it.even though i put a little grease on the bolt any lube will make it looser
the fact is there is very little holding it down but what is causing it rotate is odd
Yes, I tried purchasing one on ebay last year. Turned out the seller had used a picture of a good one and sent one with a broken rear sight. I quickly contested it and he paid for shipping back plus my refund. If you an find a 777 it has a metal sight, one of the best I have seen. I had purchased several using ebay with no problems, 777, 747 and one 717. Built up a series for myself here in Texas and my son & grandson in Ms so we would have enough to have some matches in either place. Stripped all down, new seals, orings, and valves throughout, and adjusted.power level is great, the bolt is behaving just shoot it
in the future buy a new bolt and or any parts that could be use in the future
the parts are drying up and take care of the rear sight there are no more