It would depend on the load. Lousy powder, a light charge and a loose-fitting projectile would give you much less velocity than good powder, a heavy charge and a bullet that fit tightly. The style of ignition would have nothing to do with it.
Meddle not in the affairs of dragons, for thou art crunchy, and taste good with catsup - George of Lod, Year of Our Lord 297
I always take precautions.
Beware the Evil Bullet Fairies.