So how many shots on average do you get out of your M3 before you have to replace seals?
22 Breech O ring is 5.5mm x 1.5mm Buna 70I don't believe that the number of shots would make a difference to any of the Orings except for the breach Oring and the regulator Orings. The rest would be age and the conditions the rifle is stored and used at.
What size is the breach Oring in the.22 m2 impact? I've tried to figure it out from the parts drawings but have been unsuccessful.