Whiptail
Allow me to jump in here. Heck, I'm gonna jump in anyway. CAVEAT: Plain and simple. Remingtons DO NOT play well with BP or Subs. PERIOD. Next: Classic Cowboy and Frontier Cartridge Dualist are two separate and distinct categories. You can, however, use BP in ANY category.
Remingtons have "funny" ergonomics. Before you make expensive decisions, find someone with those guns and SHOOT them. Remingtons are very PAINFUL for me to shoot. Beat hell out of my social finger.
Converting Remington Cap Guns to Suppository Shooters is a mix'd bag. R&D cylinders are set up "odd" to give 6 rounds of 45 Colt. Kirst Cylinders are set up differently. They are not necessarily Harmonious in function.
The ONLY way you are reliably going to shoot 6 full stages with BP or ANY Sub is to pull the cylinder and wipe down the Cylinder Face, the Breach of the Barrel and the Base Pin. Many claim solutions that allow them to shoot a full match without attention. HOGWASH.
CAVEAT: I don't like nor recommend 777. 777 is about 20 - 30% more powerful than BP or APP. It was never intended for Pistol Cartridges. 3f APP is marvelous stuff. Actually APP is my "go-to" propellant.
You will need Big Lube bullets. You will need to pull the cylinder and wipe down EVERY stage. Historically, Remingtons have been problematic with BP since day one. The new manufacture Remingtons are worse. Keep in mind, it those Halcyon days of Yesteryear . . . NOBODY . . . reloaded their revolver. A reload was done by grabbing another fully loaded gun. Trying to "reload" would get you killed.
Personally, I shoot Colt pattern Pietta Cap Guns (SNUBBIES) GUNFIGHTER. Or I shoot Pietta Cap Guns converted to shoot Suppositories. To keep my guns running a full match, I wipe the cylinders down between EVERY stage. I also run APP in everything. YMMV
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