Yesterday, I spent some time slugging my .45 Colt Bisley. I used fishing weight egg sinkers bumped up to the appropriate diameter , and when hammering through the bore, it seemed like there was definitely a bit of a constricted area at the threads because I had to hammer on it a good bit to get it out the last inch or so. To try to determine how much the barrel constriction was, I used another slug and hammered it into the barrel until it was about 0.5" below the muzzle and then retrieved it, but when measuring the two slugs with my micrometer, the they seemed about the same size with the muzzle slug possibly even being 1-2 10,000ths smaller. They were coming out around .4515" on both ends.
I'll probably try putting another slug all the way through the bore again to make sure I can still feel the constriction and that it wasn't possibly some missed bit of leading that was holding things up (I did clean it thoroughly prior to slugging using a brush wrapped in copper Chore Boy to get the lead out). If I do feel the constriction again but the slugs are still coming out in similar diameters, is there a more concrete way of measuring for it using range rods perhaps?
Maybe using fishing weights with a hole through the center allows the slug to "spring" a little more and it didn't fully capture the dimensions of the constricted area?
I'll probably try putting another slug all the way through the bore again to make sure I can still feel the constriction and that it wasn't possibly some missed bit of leading that was holding things up (I did clean it thoroughly prior to slugging using a brush wrapped in copper Chore Boy to get the lead out). If I do feel the constriction again but the slugs are still coming out in similar diameters, is there a more concrete way of measuring for it using range rods perhaps?
Maybe using fishing weights with a hole through the center allows the slug to "spring" a little more and it didn't fully capture the dimensions of the constricted area?