A 400 gr bullet with 150 gr of Pyrodex, for one thing I would bet on a wack in the forhead with the scopes a lot of people use for I do not even want to think about the foot pounds of recoil. I would like to have a double transducer Texas strain gage with a logiteck read out on it. Pressure has to be up.
I calculated that a 400gr bullet needs a 1-30 twist to shoot its best [thats in a 45 caiber bullet] which means that it is not over length for a 1-28 twist and with the right velocity and barrel vibration could be accurate.
What appears to be possible velocity is according to the manual 150gr RS = 1800 FPS my estimation with BH would be 1900. I would want to do some pressure testing before I tried it.
muzzle= 1900 FPS 3200 FPE [Foot pound enegry]
100yds= 1720FPS 2630 FPE
200yds= 1555FPS 2147 FPE
Muzzle= 1800 FPS 2870 FPE
100yds=1630 FPS 2360 FPE
200yds=1472 FPS 1925 FPE
For comparison a .458 win. mag has 2350 FPS with 400gr bullet and 5075 FPE at the muzzle.
Kill at one end cripple at the other? Lee