No, I have never tried FFFFg in cartridges.
Have never felt the need to try.
I think you will find that a 38 Special case stuffed full of FFFg or FFg will give all the smoke, fire, rotten egg smells you need.
A bunch of years ago I used to keep FFg on hand for 12 gauge shotgun and FFFg for all my other cartridges. 45 Colt, 45 Schofield, 44-40, and 38-40. Eventually I got tired of stocking two separate granulations of powder, so now I load every thing with FFg.
All other things being equal you can expect to see between 60fps and 100 fps more velocity using FFFg instead of FFg. All other things being equal. Same case, same bullet, and same volume of powder loaded.
Don't forget, 38 Special was originally designed as a Black Powder cartridge. That is why the case is so long. Normal Smokeless loads in 38 Special don't take up much space inside, and if the cartridge has been designed as a Smokeless round it probably would not have been so long.
For me, FFg in my cartridges gives all the smoke and boom I need.
One other thing. Before I shoot any Black Powder cartridges in any of my revolvers or rifles, I prepare them for BP. I take them apart and strip out any and all lubricants using rubbing alcohol. I clean out the oils in the frame, and dip the lockwork parts in alcohol to get all the parts down to bare metal.
Then I relube everything with Ballistol, which is compatible with Black Powder fouling.
When I clean, I use a 1/1/1 mixture of Murphy's Oil Soap/Rubbing Alcohol/and drugstore Hydrogen Peroxide. This stuff is often called Murphy's Mix. Yes, you can clean with hot water, it works fine. But M Mix works a little bit better. Plus, you don't have to get it all out again like you do with water. If you leave water down inside the mechanism of a firearm, you will get rust. That's why so many use hot water or other techniques to get the water out again. With M Mix you don't have to get it all out. You just leave it down inside. The water present in the solution does the actual dissolving of the BP fouling, the Oil Soap leaves a coating behind that will prevent rust, the alcohol helps with evaporation, and the Per Oxide gives it a little bit of fizz to help lift off stubborn fouling. Plus, you don't have to heat it, you can use it cold at the range if you want. You don't have to clean your guns the moment you get home, within a few days is fine.
Do be sure to drop your spent brass into a jug of water with a few drops of dish soap added. Do this as soon as you get home. If you wait 24 hours you will get verdigris on your brass. Rinse the brass off thoroughly until the rinse water runs clear. The set the brass aside to air dry for a couple of days until it is bone dry. Then you can reload it again.