Shot my Thompson Center caplock yesterday for the first time in a year. I successfully fired one round (first time with real black powder) and on the second round, got a minie ball stuck. It's about half way down the barrel. I will pick up the tools to pull bullets later today, but am worried that I won't be able to pull it out given how stuck it is.

Any ideas/advice? Should I use a sturdier cleaning rod and a hammer to try and seat the bullet?

It should have seated after one shot, IF the bbl was clean when you started.  If it wasn't, clean and lube what bbl you can in front of the bullet and try to pull.  If the bbl was clean, one shot of black powder should not foul it that bad.  Time for a stout ramrod and finish seating.

When we shoot BP in the .54 the bbl needs swabbed every 5/6 shots or it is a bear to seat a minnie.

You would probably destroy a cleaning rod with a hammer, but a length of metal tubing or solid rod that fills most of the bore could work.

As long as you didn't dry ball it (load with no powder) then get a wooden dowel rod just under bore size and a hammer and hammer it down to seat it, cap, fire, clean. 

I haven't stuck a ball yet, but one of these in the toolbox is a good thing to have.
Worm

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