Dave, provided there is enough 'meat' on the barrel for reboring to a larger caliber the cost is about $150 from the gs here in PA. I talked to him today and he told me he needs at least .100" remaining in machined areas like the barrel lug, screw holes, etc. Also, he can put in any twist rate you want. And, if you have a lousy bore say in .50 cal and you want to keep it a .50, he can bore out, sleeve and re-rifle the bore to the twist of your choice. Send me a pm and I will give you his name and number.