I happened upon a mid 90s Remington 700 Sendero in 300 Win Mag at a pawn shop. Since the firing pin was hanging temporarily before firing, I got it for $550. In the end there was some gunk on the firing pin spring. Cleaned it up and no more trigger/firing pin problems. Shooting some factory Hornady 150 gr SSTs, it was shooting .5-.75 MOA at 200 yds. Long story short, everything went south. I ultimately figured out that my problem was a cleaning issue. As long as the gun is clean it shoots. It looks to be more carbon fouling thatn copper though. After 12-20 rounds it wont do better than 2-3 MOA at best. So my question is should I be happy with what I have and just keep it clean? Or is there something to improve it?