Went to Cabelas in Kearney, Nebraska today, and they had the most beautiful replica 1860 Colt Army for $165 out the door...it had to come home with me.
And it did...
Black powder is a new arena for me, so I'll be doing some homework before taking her out to shoot.
Most likely you will get one that has no problems so this is to help with some standard how-to as well as what to look for if you reproduction experiences firing issues.
Do not overload the chambers, use the correct size caps and check your nipples, make sure they're the correct size.
Replacing with Tresco nipples is a good idea.
You might have to experiment with cap size/manufactures. If you have a problem with CCS percussion caps then move up to Remingtons. You'll probably have to play with size #10 and #11 (from both manufacturers) to see which works best for you, the caps must fit tightly on the nipples.
Generally, the commercially made round balls in ".44 caliber" come in either in .451 or .457 diameter. So, if you own a .44, then you must use the correct size ".44 caliber" ball. When the ball is seated in the chamber, a THIN RING OF LEAD should be sheared off each ball when it is seated. This lets you know that each ball is "tight" enough in the chamber to assure that no flames from the firing of the gun can make it into that chamber and cause a "chain-fire."
Felt wads seated behind the ball (on top of the powder) are also a good idea. Some shooters, after the chambers of the cylinder are loaded use a heavy water pump grease, smeared on the mouths of the chambers to not only provide "lube" for the ball when it is fired, but this also guards against the possibility of a chain-fire.