I use CCI #11 mag caps on my 45. But being a small bore rifle anything bigger than a #11 in primer would probably give me hammer jump. But the 54 & 58 such a nipple backfiring is less likely do to the different breech pressures I'm speculating?
BTW Minn doesn't have such tight B/P hunting restrictions Idaho has in place Five Four Bore. Only restriction that bothers many here. No scope use for Big Game Animals by those under the age of 65. Older geezers get to use em which is OK with me. Those who have been buying hunting licenses for 50 years straight deserve such breaks occasionally.
Never hurts to experiment a little. Musket caps & nipple. Its only a 15 dollar investment BUT ~~~may garner a smile "Right from the get go."