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 $550. In the end there was some gunk on the firing pin spring. Cleaned it up and no more trigger/firing pin problems. Shooting some factory Hornady 150 gr SSTs, it was shooting .5-.75 MOA at 200 yds. Long story short, everything went south. I ultimately figured out that my problem was a cleaning issue. As long as the gun is clean it shoots. It looks to be more carbon fouling thatn copper though. After 12-20 rounds it wont do better than 2-3 MOA at best.
So my question is should I be happy with what I have and just keep it clean? Or is there something to improve it?
I don't have access to a borescope to check, but I have scrubbed and cleaned with everything imaginable. I have used Montana Extreme, Bore Tech Eliminator, TM Solution, and Wipe Out. Once it fouls it is easy to clean. A couple of strokes with a brush then a couple of wet then dry patches and its good to go again, easy sub MOA. It just fouls again quickly in less than 20 shots.
JB bore paste and tight patches.I have the same gun and had a fouling issue way back with it.,Not anymore!
The carbon can be a stubborn son of a &^%$#.Get it cleaned out now and don't let it build up again.