Years ago I built a Tennessee long rifle from a Dixie kit.
It turned out really well, percussion lock that I had to inlet, .50, designed for patched round ball.


This is a beautiful rifle and accurate. I killed 3 deer with it.
Sadly Dixie no longer makes this kit.

I have no reservations about taking the biggest whitetail with this rifle but, as someone said, whatever the .50 will do, the .54 will do better.

Good luck!