I had one of those cheap twist barrel Belgian made smoothbores that Dixie used to sell. About 38 caliber. Never tried shooting it although it had proofs. One of those with the infamous scalloped shaped cap boxes. Had a 50 caliber smooth rifle, which was pretty accurate. Otherwise, I had the big stuff Right now I have the makins of a 4 bore smooth bore pistol. Finding wood thick enough was the problem. The exterior breech is 2 inches in diameter. Got a piece of black walnut log with a crotch in it and chain sawed a blank out of the lower side of the crotch. Have it drying for just over a year now.