"and if the truth were to be known, the .41 rim fire was only a little better than throwing a rock. In fact the rock would probably do more damage."
I totally disagree, after shooting several hundred shots out of 3 guns, a #1 Colt, and 2 Remington O/U. Ok the Colt and the earlier (1879) Remington had much looser barrel, even being in very good shape and gave velocities in the low 400Fps range. They would bury the bullet to the base in a 4x4", being Navy Arms loaded in Brazil in the 70s copper cased ammo I bought 7 boxes of in the early 80s. The later post WW1 Remington Derringer was a whole different proposition , having a smaller bore it would blow thru a 2x4" and almost penetrate a 4x4" because it had 600+fps velocity on that .41 bullet !
I got this pristine later gun from a long deceased local town constable who carried it wrapped in a silk hanky in his watch fob pocket during the 30s and 40s as a BUG. I carried it as such a few times in the 70s and 80s before selling it a couple years ago as part of a collection of derringers(Chicago Palm pistols, sharps pepperboxes, elliot, clover leafs, brownie and bar pistols ect.) for close to 5 figures. I sold the remaining box and a half of ammo too along with the weird sharps and other ammo .