I have a LOT of 1993 RadGreen NATO surplus 7.62 x 51 that I have shot for years in M1A, Saiga, PTR 91, various AR's with no issue. Its been about a 2 -3 MOA round but very reliable. Today I shot some in a bolt gun but had several primer strikes where nothing happened. I would load again and sometimes 2 or 3 times later it fired. The ammo has always been stored in doors in climate controlled (at least for the last 15 years or so that I've had it). Anyway is there something unique about a bolt gun that would make 7.62 x 51 unreliable or could the age of this ammo be causing it to not fire sometimes now (maybe 20% of the rounds had this issue today). The gun has been 100% previously and I switched to FGMM 308 after the issue today and the FGMM was fine. Thoughts?