Shooter’s Choice powder solvent works, but it’s slow, and it stinks. Hoppes Bench Rest 9 also works, also slowly, and it really reeks-- a sweet-sickly smell. Sweet’s 7.62 and Barnes CR-10 are both strong ammonia solutions that are faster-acting, but you must not leave them in the bore for longer than they tell you—15 minutes or thereabouts. I don’t use them because I’m afraid I’ll wander off and come back to find my bore nicely pitted. This is a criticism of me, not of them. Also, they stink of ammonia.