Short barrels...
Got two, both Piettas, so called "Sherrif's models" with 5 1/2 inch tubes.
Ones a NMA Remmie the other a 1860 Colt clone. Got a Kirst for the Remmie and an R&D for the Colt. Ordered extra stainless percussion cylinders for both
from Cabela's. Use TRM nipples, 30 Gr. fff Goex, wonder wads. 454 balls, Remington #11 caps for percussion, 28 Gr, Triple-Seven, .060 fiber wad, 250 Gr. RNFP soft lead in cartridge loads.
No problems with accuracy vs. 7.5 or 8 inch barrels, draw and ballance is better. There is more muzzle jump and flash than with the longer tubes. Probably give up 50-100 fps but I don't have a chrony so don't know for sure.
Biggest downside; LOADING LEVER IS TOO SHORT TO HAVE ENOUGH LEVERAGE, this is especially true on the Colt.
I use a "Dick Dastardly" cylinder loader so this is not an issue for me. Lever is still very useful for getting barrel off the arbor to clean/reload.
I like the 5 1/2 inch barrel length. Balance is good and it clears leather much better.
Happy Trails,
Cincinnati Slim