Some years ago I was writing for a publication called The Trade Blanket, which is no longer in print. We accumulated some BP revolvers and did quite a lot of testing for accuracy and relative knockdown power, using carefully controlled loads, consistent ammunition, and a gadget called a "Ballistic Pendulum." The pendulum didn't read force or energy directly, and only provided a comparison of with a standard, based on how far the pendulum was moved by a bullet strike -- in other words, angular displacement. The mass of the pendulum itself was constant, as was the range, and all bullet strikes were contained within a very narrow target space. The modern loads we chose to record were the displacements achieved with standard velocity 40-grain .22LR rounds, standard 158-grain lead .38 Special loads, and standard GI-issue .45 ACP 230-grain jacketed hardball loads, all commercial ammunition. All were fired in 6-inch barreled S&W revolvers except the .45's, which were fired in a Colt 1911. We tested .36 Navy replicas, .44 Army replicas, both Colt and Remington versions, and (as I recall)
two Colt Walker replicas also. All firing was done at the same distance, from a rest, using measured loads and the same powder, caps, etc., to minimize variations. We also used commercially available round ball in each caliber that were weighed to eliminate variations there, commercial wads, and lubricants.
Firing was done in 5-shot groups. The pendulum was reset between shots and the results recorded, then averaged for each 5-shot group.
For reasons I no longer remember, the magazine only ever published the results from the 1860 Army model testing, but
some of the data that spanned several models was included for information purposes. Here's what the numbers said:
The .36 Navy guns delivered energy on target only slightly greater than modern standard velocity .22 LR rounds. The 1860 replica revolvers generally delivered energy on target between that of the .22's and the standard .38 Special loads, roughly the same as a standard .38 S&W loading. And of course, the Walker replicas were the barn-burner loads.
We were surprised at the lack of response to the article.
I suspect that's why the publisher chose not to print the work we did on the other revolvers.
One of the most "interesting" things that occurred was a 5-shot flashover ignition with one of the 1860 replicas. I was taking a break and the publisher/editor chose to do some of the shooting, so he got the first-hand experience. By great good fortune (?) our photographer was taking a series of automated photos and caught the event on film. Nobody was injured, unless you consider singed eyebrows an injury, and the revolver itself survived intact with an interesting number of lead smears on the frame, the wedge, wedge screw, etc.
We did conclude that the high mortality rate associated with cap-n-ball bullet wounds was very likely just as much due to poor sanitation and worse medical care than it was to bullet trauma. It's worth noting that Cole Younger was shot
11 times during his last raid, but was captured after the gang left him in a thicket, survived his wounds to serve his sentence and went on to live to old age.