Pyrodex P is pistol grade or 3f grade if you will. A little finer then the RS which is rifle/shotgun grade or 2f. Pyrodex P works real good in a lot of rifles. I happen to like the powder. Just remember that Prodex P being finer in grade then the RS will produce a little more barrel pressure. So cut your charge back about 10%. I wish I found a store with Pyrodex P for that price. They would not have anymore when I walked out of there...