[Unclenick]

You'll have noticed the rifle has no barrel/cylinder gap. The bullet may go through the rifle without loosing half its copper just because it doesn't have gas escaping through such a gap cutting plating loose on its base. Rifles can also usually tolerate more absolute pressure.

Strong crimps are necessary in the revolver to keep the recoil from backing bullets out in the cylinder. You don't want to give that up. Getting a cylinder reamed to maximum chamber dimensions is a standard revolver smith's accurizing step. You also want, with the gun empty to look down the bore and see that the chambers center well at the back of the barrel when the cylinder advances and locks in place.