Yes, you can get a double rifle to regulate with a lighter projectile within a minute of grapefruit by tweaking the charge.

Basically:

.577 --> 650
.500 --> 440
.470 --> 375 (cast bullets for .475 Linebaugh)
.450 --> 350
.400 --> 300
.375 --> 235
.350 --> 200

These have work fine for me in each of the calibers in a double rifle.

B.