I was able to try the .562" balls, with .020" patch, and it did shrink my group, from 5.5" to 4" on average. For hunting, I'm more than pleased, and the 1861 is mostly my "back up" rifle when hunting, in case of extreme wet weather. Otherwise my Jeager is my go-to rifle. And I do like to get the '61 out once or twice, just because it's such a cool rifle. But very heavy. !!! But here's the weird thing, or surprise. Just for fun, I experimented with putting some bondo in the base cavity of some .575" minie's I have. These bullets will free-fall down the bore. So I coated them with hot bee's wax. Requiring a firm push to press them into the muzzle, they then slid nicely down the bore like a patched ball. Expecting no good results, and just hoping they shot well enough for a quick follow up shot, I touched one off over 100 grains of fffg. Dead center in my paper plate, same exact POI of the ball load. Wow. Shooting some more, turned in 4" groups just like the ball and patch load. Same POI and POA. Wow. Here is the mystery. Two out of ten shots didn't even hit the back-stop, 4X2'. If you look at the pic of the target, and the close up, you can see that they are very well stabilized. To have completely missed my target board, those two must have tumbled. But why. Also, I have had bullets tumble on other occasions, different guns, and they still hit the target board. I trust them (the minie's) enough to use for a follow up shot. I would not trust the load to not tumble on the first shot, which of course would not be good. The rifle will be loaded with patched ball for the first shot, and then the slugs for quick follow up, being really fast to load. No short starting, wads, or nothing. I found they also loaded easy in a fouled bore, and stayed in the 4" group regardless of the barrel being clean, or fouled. And of course, if I can get a string of ten or more to stay in the group, and no fliers, we may just choose that as the load, for that rifle. It's certainly powerful. Okay, some food for thought for y'all. I believe that on the two wild shots, the plug failed to expand the bullet, for who knows what reason. I have read up on base plugs in minie's, pritchett bullets, etc, and know that bondo is not ideal, but it sure worked for eight out of ten shots. So.........???? Thanks for listening.