Loading a muzzleloader is about the same as handloading a rifle cartridge or shotgun shell for a modern weapon. The only real difference is that with a muzzleloader, you are putting the powder down the barrel, followed by a projectile, and then putting the primer (cap or pan powder, in the case of a flintlock) into a mechanism on the outside of the breech instead of into a primer pocketin the head of the cartridge.

The Brown Bess smoothbore flintlock musket can be loaded and fired 15 times in 3.75 minutes by a trained "recruit in the Continental Army". Does this sound slow? The only advantage I personally can see to the "modern" muzzleloaders" is that the breech plug can be easily removed so you can clean the thing from the breech. Butthis is a definite advantage.