Just how satisfied are you with your barrels accuracy? I am getting pretty serious about getting one of these barrels but I understand that the groove diameter runs about .379 in these barrels, which would be period correct, but these days .375 is the more common groove diameter of rifles in this caliber range and jacketed bullets larger than .375 are scarce. That may not matter as a custom mold can be had for something on the order of $70.00.