I have a Krag sporter with a Smith Corona 03/A3 4 groove barrel.
A pound cast was quite satisfying and it shows a nice .300 bore and .308 groove diameter.
The throat is much shorter than your standard Krag. I doubt the 311284 would chamber.
My goal is to use it for targets at 100-200 yards. Velocities of 16-1800 or so with gas check boolits run through a Lyman 45. Feeding through the magazine would be nice but not essential. It will never hunt unless a groundhog exposes himself at the right time.
Both of the boolits mentioned would be good candidates, but which mold to buy first?