The .45 TC's that I have had experience with were some of the most accurate rifles I have shot. 1/2" 50yrd groups were common for them. I found that every one of a half dozen I tested or, recommended the following load to, would shoot at, or near, this accuracy level. The load was 60 gr. fffg, at the time, Dupont powder, .451 ball, yes, .451. with a .011 to .012 cotton flannel patch. The ball size requires the use of a starter, but once in the bore, they slip right on down. The TC's of the seventies were button rifled, which makes for a very smooth bore finish, although considered a bit shallow, I believe around .005, can't remember for sure. Mine would tear the X out of the X ring at 50yrds all day long. I set one up for a preacher once that shot consistant 3/8" groups at 50 yrds, but maybe he had outside help. I do not know if TC still makes barrels of that quality today, but before you buy a different barrel, give what you have a try, but also consider better, finer sights. I also should add that for some reason, in order to maintain that accuracy level, I had to replace their stainless nipple about every 100 shots. I do not understand that part of it, but that is how it worked. I also found that I had problems duplicateing that performance with any cap other than Remington. I have no explaination for that either.