Phil - this question was asked me a while back by someone who wanted to purchase a traditional rifle. They were interested in the Lyman Trade Rifle and IM'd me asking for my experiences with my Trade Rifle. Their concern was the 1-48 twist and the idea of shooting a roundball with enough velocity to take care of hunting situations. I told them my load was 90 grains of Goex 2f and a .530 roundball. The accuracy was excellent and their worries were unfounded from my experiences.

As I told them, I have a number of Thompson Center rifles also with 1-48 twist. I have heard all the claims that the 1-48 twist will not shoot roundball all that well or with good velocity. Well all I can say is most of my 1-48 twist rifles and roundball shoot between 90-100 grains of 2f & 3f powder depending on the model. Also the accuracy I achieve with these rifles that some claim will not shoot roundball is amazing. Plenty of hunting accuracy and even some finetarget accuracy with the right sight.

According to charts (T/C manual) a .54 caliber roundball with 90 grains of Goex 2f produces 1761 at the muzzle. With 100 grains you move to 1855. In the .50 caliber 90 grains reads 1950 and at 100 grains we move to 2052 fps at the muzzle. I quote those charges because of my many rifles they are the common charges I shoot for hunting with the 1-48 twist and I get excellent accuracy. That is some impressive speeds.