Can you share some details of the "freshening" process................very interesting!!!
I think I’ve posted before and Uncle Jim Everett has as well. It’s a lot of work and unless you really want it done the old time way AND preserve the form of the original rifling and do not want to have a big caliber jump you should send the barrel out to be re bored and rifled or lined.
1) determine if barrel is salvageable without cutting at muzzle or breech. If the breech is so eroded that there are zero traces of rifling left, we are looking at cutting at least 2 calibers. Figure 1 caliber per full work day. Make sure the remaining rifling is strong enough to turn the rod with a tight wad on the worm.
2) clean barrel bore as well as possible to remove loose rust using a worm and coarse steel wool lubed with oil. Lube the bore.
3) drive an oversized ball into the muzzle. Cut off the flash and short start it then drive it through to the breech. Measure and inspect it. If the lands or grooves look stripped, send it to Bobby Hoyt to rebore it and rifle it.
4) Now it’s time to set up a lead lap for freshing the bore. I get a hickory rod to fit in the bore without much slop. 2” from one end file a square on the rod about 2” long. Leave a half an inch round at the end. Below the square area file a slot around the rod. In the square are file some notches to “grab” the lead lap. Slide the rod into the muzzle with the designated lap end sticking out the muzzle. Wrap string in the slot below the lap area till It makes the rod a snug fit. Plenty snug. Slide the rod into the bore further till the square area is just into the muzzle.
5) torch heat the barrel while melting lead in a ladle. Get it hot but don’t unsolder anything! Pour the lap. Let cool and trim off the flash. Measure it at the deep and muzzle ends. You probably have to do some filing and trimming with narrow chisels at the muzzle end. Do what you have to do to get the lead lap to go through the bore end to end.
6) now you need to make cutters. I use 1095 flat stock. The land cutter needs to span across the edges of the grooves and it should be rounded like the bore. The groove cutter must be within about 0.001” of the groove width and square edged. I hand file teeth about 12 per inch.
7) inlet the cutters on opposite sides of the lead deep enough to slide through the bore un encumbered. Now start shimming them up till they cut. Use thin paper or foil shins 0.0015” thick.
8 get to work cutting groove by groove and land by land shim by shim for many hours.