Many of the newer Hawken rifles had a 1-48 twist but there are some strange ones out there also. And they normally shoot a patched round ball real good. I would first identify the twist of the rifle. then if it is a 1-48 or 1-66 load 80 grains of 2f Pyrodex Rs powder and a .015 patched roundball and see how well it shoots at 25 yards. Good luck with your rifle.
Also I commonly misspell the word Hawken as Hawkins. But I never let that bother me. Neither should you. Many people use the word Hawkins to describe their rifles.
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"Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, a total wreck, screaming Yahoo, with a big smile on your face."
In a percussion model, you can use, IN LOOSE ONLY FORM... American Pioneer Powder, Triple Seven, Pyrodex RS, Pyrodex P, Jim Shockey Gold 2&3f, Pinnacle, Goex, or any black powder for that matter, just about any powder out there EXCEPT Blackhorn 209.
As for projectiles, you can shoot round ball, conical bullets, ball-ets, even sabots. I shoot a 250 grain XTP out of my Hawkens rifle with good accuracy. You can shoot powerbelts, Thors, and any of the other conicals on the market like maxi ball, maxi hunter, etc. Some will shoot better then others.
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"Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body, but rather to skid in sideways, a total wreck, screaming Yahoo, with a big smile on your face."
I have had EXCELLENT results shooting TC's 1 in 48 inch twist barrels with patched round ball or conical. I always got a couple yards of "pillow ticking" material from the fabric store, and used ..495" swaged balls on 100gr of FFg Goex. Most of my shooting with roundball, but off and on played with Great Plains and Maxiballs.
Renegade and New Englander both bought new, would vertically string shots until they had about 50-100 shots through them. Could speed up the polishing process with some steel wool, but hey, shootin's fun!
All three (2 Renegades and 1 New Englander) were older guns, did not have QLA muzzles.
My newer Hawken Silver Elite, was tempermantal for a while but has since come around. Polished, then went to BP substitutes, musket cap nipple............it puts conicals in the black now with regularity. It has a QLA which I dislike, but it's pretty and shoots good, plus took my largest deer to date, so it aint going anywhere
Not sure what all factored into the fliers back then, but it's consistently good now.