Yeah I was told about 15 years ago that 80 grains is max for 3f in a 54 cal. My one TC Renigade shoots great at 75 gr. of FFF Goex never has missfired I use 85 gr in both my 50 cals and want to try it in mi Pro hunter 209x50
With Swiss black powder...2fg is perfect for my 54 cal flinter. 3fg Swiss blows patches...a tad too hot. I have shot the 3fg Swiss out of my White Super 91 .504 cal. inline & know a lot of guys that use it with outstanding results.
I prefer Goex and Swiss 2f in my TC .50 flinters over the 3f because my rifle prefers it. I do use Goex 3f in my RMC to shoot sabots and it likes it. I need to test it out with the Swiss 2f and see how it does yet. I don't think there is a pressure issue using 3f in a 50/54 but I think you have to let your rifle tell you which is better
I think alot of people who use the 3f do so because they can use 1 granulation for charge and prime. Some of the experts I have talked to in the past claim that a flinter should use the 2f over the 3f for a more consistant ignition. I like the 2f with a patched round ball and the extra speed from 3f isn't worth much in power, range or trajectory.
Our family of flinters uses Goex FFFg in all our sparkers; .36, .45, .50, .54, and .58 calibers. We don't push the loads in any of these guns because they perform quite well with reduced charges of powder. More isn't always better with black powder.
Common sense. 3fg is a little faster and a little higher pressure than 2f. If you go pushing envelopes it could have disastrous effect. The old rule of thumb was 3f for anything 45 cal and under and 2f for 50 and over to perhaps 75 cal and over where folks suggested 1 fg
Modern steel and manufacturing produces much tougher steel and barrels. Modern Guns can usually handle a hotter powder within reason. Just don't go putting 150 grains of 3fg in a 10 guage shot gun with a twist barrel. You may actually get away with "super loads" in big bore guns, but then again, you might not. Why risk it.
Not sure how many know this but blackpowder is the same Fg,FFg,FFFg,FFFFg,etc.The difference is size of the screen it fell thru.Smaller the grain Fg,the faster burn because its small.Sticks burn faster than logs but its still wood.You can take FFg,put it in a film canister with a lead ball,shake it,and get FFFFg or finer.All my small calibers like FFFg.Larger get FFg.Some of my 45's like FFg.,some like FFFg.
My youngest Son has a custom Flinter ,in .54 cal., that we could not get to shoot worth a hoot with 2F. Finally out of frustration tried the 3F. He has been winning a bunch a stuff ever since!! This Flinter was made back in the seventies and will still one hole them at 25yds.
For deer hunting with my flinters I load 70 grains of Goex 3F in my 50, 75 grains in my 54 and 80 grains in my 60 and have killed deer with all of them (54 is my favorite). Used to use 2F in the 60 but found 3F works just as well or better with the moderate loads I use. Now I don't have to worry about grabbing the wrong powder can.
Never tried the Swiss powder, would like to but have about 5 lbs. Goex to burn up first. Guess I need to shoot more
Sure thing Bunky that makles sense to me too. I use 75 to 80 gr of 3F GOEX in my .54 flinter and have used 4 F without any problems. BP shooters need to understand that BP is measured by volume so when using finer grained powder for a main charge - back off on the volume and build up to a good charge. One of the things I like about ML shooting is how different loads can effect performance.