Well now . . . let's see what Thomas DID say about slow vs fast-burning powders. To summarize the facts of the tests conducted by IMI:

"They involved the firing of many thousands of cartridges by a team of nine experienced shots of varying build, shooting under a wide variety of conditions with guns of different types, weight and boring. The cartridges were all loaded to give the same velocity to the same shot charge, though by means of powders of various rates of burning. The shooters did not know what they were firing, but were merely required to give marks for recoil. They were unanimous in assigning the lowest recoil to the cartridges with the fastest-burning powder, the dynamical effect of which was checked throughout by electric accelerometers built into the stocks of the guns, and their conclusions have since been widely confirmed." Gough Thomas, "Shotguns and Cartridges for Game and Clays", p. 155.

That seems to be a pretty complete description of the test in question. I'm sure more thorough than a hillbilly from Tennessee or a jack pine savage from the North Woods of Wisconsin can do. But if Mr. Miller would care to conduct a test of his own--with witnesses, a group of experienced shooters, etc--I'm sure we'd all eagerly await the results.

But one question for our resident hillbilly: What difference does it make to a powder company whether they promote a fast-burning powder or a slow-burning powder? Both have their advantages. As noted here, the slow-burning powder produces a lower peak recoil, which some people may feel is advantageous. On the other hand, you use less of the fast-burning powder to produce the same velocity, which results in cost savings to the individual choosing that powder for reloading. So both--for different reasons--are going to have their fans. And powder companies all seem to offer a wide variety from which to choose, for whatever reason the reloader decides to make his selection.

And it probably should be noted that in Hatcher's formula for measuring recoil, the powder weight is multiplied by 1.75. So although it's far lighter than the shot charge, it's a more significant factor than just the weight of the powder compared to the weight of the shot.

Last edited by L. Brown; 08/18/18 11:03 PM.