54 Cal buffalo hunt accuracy issues

[ike]

I am going to South Dakota in a couple of weeks to hunt a buffalo. I have two 54 cal muzzleloaders to use. One is a golden age classic from TWO and one is a TC Hawkin in 54 cal. I am loading with 90 gr of goex 3 f powder and a 530 round ball with a .014 pt patch. I can hit a two-inch circle with them if a have 50 0r 60 gr 3 f powder. I think I need to be loading with at least 90 gr powder to get a load that will kill. I have told the outfitter I need to be within 50 yds. I cannot get groups to be within 8 inch circle. I am using bear grease for a lube and that solved my issue a couple of years ago with cold weather accuracy, I am 75 years old so i have a tripod to steady the rifle but i have my hand under the barrel resting on the tripod. I am looking for any suggestions you may have to get a better group. I have been told that i need to take a lung shot, Thanks for your help or your experience. Ike

 

[waksupi]

I think you would be better off shooting them right behind the ear. Just penetrating a winter coat and the thick hide is a chore for a round ball.
Increasing the load to around 120 gr. 2F may work better for you for the accuracy problem.

 

[sb 54 cal.]

Drop down 5 grains and try. 3f might not be what they like.