Make sure it is timed right. I've read about a lot of them not indexing properly.
Unless someone was discussing a model that just didn't rotate due to a broken hand or something, I can't imagine how the timing would be off. By the very nature of their design, indexing is generally not an issue with pepper-boxes--at least not the Allen versions. Unlike standard revolvers, there is no need to line up a cylinder chamber with a single barrel since the cylinder and barrel are one in the same. The only requirement is that the hammer comes in contact with the nipple. That's why the hammers on these pistols are a relatively broad flat bar. Basically it makes no difference at all what position the barrel is in when it fires since there are no obstructions in front of it. Of course this is not the case for single barrel revolver with a cylinder mounted in a frame.
There also is no cylinder lock up like a conventional revolver nor is there really a need for one.
There are two concentric ratchet groups milled into the rear of the barrel group. Just outside of that is a ring of six milled shallow detents. Extending from the frame is a coil spring driven broad pin that interacts with the detents holding the barrel group in position that lines one nipple up with the hammer.
There is a hand much like a standard revolver which only has to revolve the barrel group to an approximate location and then the spring loaded pin and detents take over to force it into the approximate proper position for the hammer to hit the nipple. There is also a small pin under the arbor that is forced forward into the inner ratchet group as the trigger is pulled. If for some reason the barrel did not rotate into the proper position, that pin would stop one from pulling the trigger far enough to drop the hammer. That pin locks the barrel into the proper position until the trigger is released.
Once the trigger is released, the barrel is not locked in place at all and even with the hammer down, one can easily rotate the barrel group because it's only held in place by the spring pressure of that pin riding in the detents. This sounds more complicated than it is, but the bottom line is that timing issues are relatively non existent because the design does not need the precision that a conventional revolver needs.
This is one of the reasons that Ethan Allen could design a relatively simple, effective, and quite inexpensive double action revolver that outsold just about any other repeating pistol up until the 1850's His design simply did not have to worry about exact timing nor a fixed lock up which in turn made them cheaper to manufacture
Of course the downside of having a bunch of revolving barrels is that there was no way to effectively aim down the barrel since it was almost constantly in motion nor was it exactly accurate much past the other side of a card table--being a short barreled smooth-bore.
When Colt finally came out with the 1849 Pocket model and then the 1851 Navy, their compactness and increased accuracy advantages began to outweigh their cost disadvantages compared to the cheaper pepper-boxes. Consequently, the Colts and Colt imitators began to dominate the market. Still the pepper-box survived well into the mid 1860's. However, since they could not be converted to breech loading like a standard revolver, the advent of the self contained metallic cartridge marked the final nail in their coffin.
Cheers
P,S,
Here's a video from the Cap and Ball channel, which helps explain how the action works better than my description although he doesn't mention the pin under the arbor. His model appears to be almost identical to mine and I understand these are one of the most common. Allen manufactured these guns over several decades at several different factory locations and names. There are no factory records as to the changes from one to the next nor serial numbers to go by.
They made some up to .36 caliber with 6 inch barrels. These were referred to as Dragoons and were the most popular for the forty-niners. Allen also made one single action version which has a hammer with a spur for cocking. However, I have no idea as to the actual mechanics.
All in all, collectors have identified 25 or more distinct models. My Flayderman's guide lists 26 models. Allen had imitators too, so there are quite a few similar models out there, not to mention English and European models that were imported.
