385gr Great Plains velocity

[samsmix]

I'm not brand new to muzzleloading, but have not done a lot of shooting with conicals. What kind of theoretical speed should I be getting from a 385 grain Hornady Great Planes over 100 grains of Pyrodex RS? Barrel is 24 in with 1 in 28 twist

 

[Centurion]

Caliber? It is just to guess more accurately. But considering Lyman's handbook, almost any bullet of 330 to 380 grains, of 50 to 54 caliber, on top of 100 grains of Pyrodex RS, should give you about 1400 to 1500 fps.

 

[Centurion]

If it is a 50 caliber, the Lyman's handbook reads 1363 fps for a 395 grains bullet with a barrel of 24 in, 1-48 twist rate.

 

[samsmix]

Its a .50 with a 24" bullet shooty pipe thing, 1:28 twist. As near as I can figure it must be about 1400. I had been trying to calculate long range trajectory (by muzzle loader standards). For its similar BC, I used .45 ACP 230gr Ball @ 1400fps data from Hogdens manual. This got me on 30" paper at that distance, and I corrected from there. I can sightbon +2.5" at 100, be on to 150, and hold 18" over a deers back at 200. The load gives me a 7" group at that range, making it maximum yardage.

Sorry for the delay.