Bill Akins wrote:
Now how could I utilize that piston to also rotate the cylinder without the cylinder having to have zig zag slots and recoil rearward?
Ah! I've got it. The arbor pin/gas piston could have spring loaded lug projections on it that would pivot backward but not forward. The hole in the cylinder for the arbor could have corresponding spiral slots cut into it so that the lugs on the arbor pin/gas piston, were just barely engaging the spiral slots in the central cylinder hole. Then when the gas piston went rearward to cock the hammer, it would also advance the cylinder.
Stephanie B wrote:
Sounds overly complex to me. If the arbor pin/gas piston is pushing back on the hammer, then why not just utilize the single-action mechanism to also rotate the cylinder?
Early on, I thought about doing exactly that Stephanie. And that MIGHT work. But I'm afraid the violent. abrupt force of a gas piston directly against the hammer might be too much without some sort of delay, and cause the cylinder pawl to break and or cause the cylinder to rotate so rapidly that it might overtravel faster than the bolt could drop to lock it in place.
On cartridge semi-autos (unless they are low powered straight blowbacks) you have to slow down
the extraction of the cartridge (slow initial extraction) so that the cannelure (rim/groove) of the cartridge case isn't ripped away. The same is true on a semi-auto action using a sufficiently powerful load. You have to slow the action down or risk breaking parts.
If you don't slow the operation down in this instance, it could break delicate cylinder pawl, or wear its end and the ratchet on the rear of the cylinder and also cause that too fast over rotation of the cylinder I was worried about too.
For instance the Steyr Hahn model 1912 semi-auto pistol using a delayed blowback system for it to operate. The Steyr Hahn has big angled lugs on its barrel that ride in corresponding angled slots milled into the frame. The frictional interface of those lugs causes the operation to slow down and also partially rotates the barrel. Also known as "retarded blowback" or "delayed blowback". This enables that pistol to operate without the action being so violently abrupt that it breaks parts, rips the cannelure off the case, or won't operate at all. See the big angled lugs on the Steyr Hahn's barrel and the angled slots on the frame here.....
When I get around to experimenting on making a semi-auto muzzleloader out of a old beater 1858 Remington revolver, the first thing I will do is drill out the nipples and try to get that extra gas force to blow the caps back to fully cock the hammer which as you noted would also rotate the cylinder. It is possible that the cylinder pawl and cylinder ratchet may take the stress without breakage or galling, and it is possible that the cylinder may not overtravel faster than the bolt can drop to lock it. But I have a high probability of fear that I will encounter problems. But it's still worth an initial experimental try to see.
Then if I find that not slowing down the operation of directly blowing caps back against the hammer to operate the revolver doesn't work and is too violent and abrupt, then I will also know that the same would be true of non delayed piston acting against the hammer. In that case I would have to go back to my ideas for slowing down the operation using some form of delaying the operation of the system so it isn't so violent and abrupt.