We got out in the woods this afternoon with a recently acquired D.H. Hilliard underhammer. The smooth bore measures .525". The nipple cone was a lot larger in diameter than a number 11 cap, but much smaller than a musket cap. Was there ever a civilian cap made that was bigger than a #11? I chucked the nipple up in the drill press and filed a good taper on it, and got it to where it will hold a #11 cap well. I loaded it up with some 7.5 shot and fired it a few times, killing a couple of Coke cans deddern’ell. It had a rear sight at one time, but it appears to have been filed down flush with the barrel. It has been well used, and fairly well taken care of. The stock has had some repair, a couple of cracks and a chip. I like seeing the old repairs and don’t mind stable cracks. Adds character. It was still good and solid after carrying it a mile through the woods and firing it a few times. The bore is mostly bright with some light and scattered pitting. Doesn't fuzz up a cleaning patch too bad. Still needs a little work with some JB paste. The squirrels eluded us once again.