Not at all interchangeable. If you have a rifle, modern .450 NE 3 1/4 Thin Rim as made by Jamison works fine and uses ordinary LR primers. May need fire forming, but that is all. The coiled cases are collectors items only. I would not assume that they are safe to fire, even if the old primers (what size & type?) worked.

My Alexander Henry dates from 1869 & uses .469 bullets.