Remember me saying my Peter Berry flintlock had 12 inch groups, and it was driving me nuts? I bought .50 caliber minieballs from Track of the Wolf. They slid down pretty easily with a bit of coaxing. 5 inch group, so far. I'll take that. These are true Minieballs, not flat on the back. Now I have a spin to the bullet.
On the 1842 Springfield reproduction I'm not sure. Stupid Armi Italian thing has no breech plug! I broke the bolt for the rear sight trying to take out a breech plug it doesn't have. Amazing! How much trouble would they have had to go through to put in a breech plug? I thought it had one, but looking really closely I don't see a line at the breech. Now I get to tap a hole, that is, after ordering an M4-.70 tap set. The few minieballs, .69 caliber I shot were IMMENSE! They shot low. So I guess I have to up the powder load. I've read that you get leading if you overdo it, but they are about a foot low at 75 yards, compared to the balls. You can barely see any rifling, but it's there, vaguely. We'll see if they work. I took out the nipple, and will try trickling in powder, then blast out the ball and patches. I had to quadruple up patches because the bore is so big. That's how I got the rascal stuck. I unscrewed the cleaning rod, and, of course, the jag is still down there.