Finally got the chance to shoot the T/C Hawken 54 today that I got from tomhargrove. The 1:48 twist works great with PRB, just like everyone says. It's easy to load and fun to shoot. I have to replace the blade sights with more age-and-eyesight-friendly peep sights, but that was a known factor. Since it's just become my favorite smokepole by far, I won't have any qualms about springing for the peep.
All the folks that have said they really like their Hawken / Renegade in the 54 calibers... now I know what you mean.
I experimented with the loads, at both 25 and 50 yards. She likes 40 grains, 50 grains, 60 grains, 70 grains, AND 80 grains. I couldn't believe it, but this rifle shoots sweet at such a variety of loadings that it's amazing. I'll have to have better sights to be able to tell for absolute sure, but as best I could tell the accuracy was good all through that range of loading.
I was with a friend who was shooting a new-to-him AR-15 that was not ejecting perfectly and was kinda frustrating him. There wasn't any question who was having more fun. He even shot the 54 a couple of times and liked it.
Keith