Hello Ethan,
I would look into the traditions deer Hunter with 1:48" twist barrel.
Or check around for used one and also look for a used Thompson center hawken/renegade or Lyman rifles.
Make sure to check the bore for putting or a bulge when buying used.
That would be a good place to start.
For...
That's some good shooting JJB22 and sounds like you had a great time.
+1 on getting more BP fire arms.
Good range report but would enjoy seeing some pictures of your rifle. :thumbsup:
Howdy and Welcome fellow PA'er. :hatsoff:
For F&I war information you might try county historical societies and maybe try Cornwall Iron Furnace might have some information.
I have an Armi San Marco 1860 & Pietta 1860 army's and shoot 25 grains of Goex 3F with a .454 round ball om both.
I cannot say about the 1851 until I get one,I fell in love with the accuracy,feel and balance of the 1860's.