Yes in some cases, the cost per shot can get very expensive when shooting muzzleloaders. A lot of it depends on the cost of your projectiles. That is one reason some projectiles like Barnes, Nosler, Powerbelts, and Parker you really have to be careful about your shooting costs, or simply do not thing about it and spend the money.

Buying bullets in bulk, sabots, primers, etc will help reduce your over all costs greatly.