First muzzleloading rifle - a Hatfield .45 - and cap size confusion

[Ugly Sauce]

Regarding the use of a musket nipple, please be sure the recess in the hammer nose is large enough to accommodate a musket cap, and that it is well-centered on the nipple when at rest. If not well-centered, some heating and bending of the hammer may be in order.

Wishing you success in your endeavor.

Good advice for everyone. I wonder how many people have been un-able to figure out ignition problems, because the hammer was not hitting or sitting square, on center and level on the nipple. Easy to overlook. The hammer on my Lyman Plains Pistol does not sit perfectly square on the cone, so yeah I plan to do some EL-Bendo Heat-O on the hammer, although it has never ever miss fired or hang-fired. It's that OCD thing again.