Originally Posted by
Don McDowell
I'll about bet it has been chambered for the 3 1/4 case at one time, but it was with the tight paper patch chamber. Any bullet over .450-454 diameter isn't going to chamber. Unless it's one of the really short 300 gr express bullets.
You might see if you can get ahold of some .444 slicks and wrap them in 8 lb paper, if you don't have his mold. Over 120'ish grains of 1f powder a .060 fiber wad, a 1/16 grease cookie and a thin wad punched from wax paper or a playing card.
Neat old rifle to be sure.