For the most part, I like fffg.It has a faster ignition then the ffg. Plus, I shoot mostly flintlocks & I want as much help that I can get with fffg.

However, if I'm using the CVA -Sharp Shooter, I seem to get better results from it. Not sure why, but if this is what this rifle likes, then why puss my luck & use something not as accurite.

On some ocations I will take my ffffg priming powder & crush it up even finer then it already is. I use this on one of the Italian Imports. It isn't the greatest rifle, but with serve my purpose.

Just substitute it for what you are measuring now, you will probably not see much difference in velocity. Back in the late 60's there wasn't much FFG around and all I remember shooting was 3F in stuff up to 58 caliber.