A while back I bought a TC thunderhawk 50 cal black powder rifle. It has the 1:48 twist, and shoots round ball rather well, but I was not able to shoot any conical bullets better than 24" at 100yards. The lightest bullet I could find at the store was 350 grains.

I finally decided to cast my own 250 grain bullets from a Lee mould. The Lee mold casts a bullet that is only 0.6 inches long. Using pure lead resulted in poor accuracy. But using wheel weights gave me much better results. The bullet was rather hard to push down into the barrel, but I never got one stuck half way. I put 5 shots into a 3" group, with the six shot out 8"

I posted about my problems on the net a while back and a few people mailed me asking if I had any solutions. This is the only bullet I have found that shoots well in the thunderhawk other than the round ball.

Ranb

I have a Thunderhawk and I think the twist is 1:28. My most accurate load was a 44 JHP in a sabot with 90 gr FFG black. Three shots under 2" at 100 meters. Sent it in to TC for a minor repair and they sent me a brand new barrel. Hope it shoots as well as the old one.
Greg

I have a TC Fire Hawk. The Thunderhawk has the exact same barrel on it and as far as I am aware, they were only made in a 1 in 38" twist. I would be very surprised to see anything different than this.

Mine has shot the lighter weight sabots quite well, but by far the most accurate bullets have been the No Excuses Conicals. These are heavy conicals that have shot extremely well. I regularly get 2" goups at 100 yards with a peep sight and front bead.

Good Luck! FH