Before we get started, I came up with these loads before reading the label and seeing that Hodgden's says not to use Triple-7 FFFg in cartridges. I do not recommend that you disregard Hodgden's advice, I am merely reporting my experience. If you choose to use these loads you do so against the manufacturer's recommendation, and entirely at your own risk.
It's a PITA to get actual black powder around here, and in the way-backs when I was shooting percussion revolvers I found Pyrodex to be more problematic than Black powder, so I wasn't eager to use it. I did a bit of research on Triple-7 and decided to try that. I've dismantled some 19th.C European cartridges loaded with 'revolver powder' and determined that this appeared to be FFFFg, so I decided to try FFFg Triple-7. I measured the amount that fit comfortably under my bullet of choice, weighed the charge and based my load on that. This load is very lightly (barely) compressed. I fired them first in a test gun to check for any problems, and when there were no signs of issues I tried them in my Webley Model 1883 RIC with a 2-1/2" barrel. These were the chronograph results-
210gr. copper-washed LSWC, 7.5gr 777, Federal #150 primer
551 fps., 142 ft./lbs, SD: 9
Loads were very consistent, acceptably accurate and recoil was notable in the lightweight pistol. The velocity from the gun's 2-1/2" barrel was about what I expected, given that original loads are reported to have made 750-775 fps. from the 8"-barreled Adams revolvers they were designed for.
This group was fired off-hand, single action at 7 yards. Being me, of course, there
had to be a flyer.
Brass was un-damaged, and cleaned up easily with mildly soapy water. Cleaning the guns was similar to cleaning up after smokeless rounds. I was quite pleased with this result, and have used this load regularly in this gun with no issues.
That being said I am simply reporting my experience, and do not recommend disregarding Hodgden's advice not to use this powder in cartridges. I'll continue to do so, as I have encountered no reason not too in any of the several cartridges I have used it in... but it's been noted that I am not always the sharpest spoon in the drawer.
Frequently.