I like the Montana Extreme cleaning products, but there are members on here that forgot more than I know. My limited experience is, gun doesn't just stop shooting good, and there is a right way to clean a bore from copper fouling.
Copper fouling. Make sure to clean with a copper removing product and white patch until no blue residue.
This is the product I've been using.What kind of cleaning solution are you using. Usually when a rifle just stops shooting the barrel is fouled out. Tell us what you use to clean your barrel please.
Shep
I shot those groups for 3 months consistently, even out to 600 hundred yards I was hitting pop cans consistentlyHow many groups did this rifle shoot that were like the target posted when it was shooting good? Those other groups are probably what 2.5" at 200 yards? It could be alot of things. Mirage, ammo, scope parallax or you as the shooter. That first group was really special but I'd highly doubt a hunting rifle would produce those groups on a regular basis. We all have those groups where the stars align and everything came together...or at least the bullets did. I'd still want better accuracy then what your getting as well.
This is the product I've been usingNothing shows up on my side showing me what your using. Maybe try again. Really sounds like copper fouling to me.
Shep
I don't see anything on the label that specifies it is for gun cleaning ( maybe I'm just not seeing it). What I do see is that it says is it penetrating oil. Switch to a product made specifically for cleaning the fouling AND copper from rifle barrels.This is the product I've been using