This is a rather complex subject but to try to make it as simple as possible with the least conversation here goes: Real Black Powder is a combination of sulfur, potassium nitrate, and charcoal and the granulations as stated are the ff markings. Real black powder is probably the oldest and most reliable of all the powders but also nearly the most dirty and very corrosive if not cleaned very soon after shooting. Pyrodex was one of the first "substitute" from here on referred to as "Sub" powders. It is also nearly as dirty and corrosive as real black but can be handled and sold like smokeless powder and does not require the special handling real black powder needs. Then came some of the ascorbic acid "sub" powders which some worked and some did not (these are Black Mag'3, American Pioneer, Shockeys Gold, Pinnacle and some others). Then Tripple Seven came around and it is similar to the ascorbic acid powders and somewhat similar to Pyrodex but a little cleaner than Pyrodex but can make a bad crud ring just forward of the powder charge area in some rifles. Most of the subs are more subject to deterioration with age than real black powder. Most of them are also subject to gathering moisture which affects the power with age. Real black is the easiest to ignite and the subs range in that area. One of the newest powders is Blackhorn 209 which is for all practical reasons the closest thing to smokeless powder that can still be used in a muzzleloader. This new sub is very difficult to ignite and many rifles will not shoot it without either hangfires (late ignition) or no ignition at all. It is probably the cleanest of all the muzzleloading powders but not easy to use due to the high ignition temperature. My recommendation is to either stay with Pyrodex (which has been reliable for many years) make sure to clean the rifle well after shooting, or go with Tripple Seven if your rifle will handle it as it also has become known as being reliable and repeatable in many rifles. You need either ffg or fffg granulations. Primers are another subject altogether and I think this is enough for now.
