Yes, but what about his velocities ?
I cannot speak about Ackley, but I suspect his thinking was the same as many of the time. Ackley and Canadian gunsmith and experimenter Ellwood Epps had many discussions via the phone and in letters about improved cartridges.
I can tell you what Ellwood Epps used to say about the 303 Epps improved cartridge - if you can get 12% more powder into a case, it stands to reason that the velocity will increase by at least that much, and probably more. Physicists of the day would have known that wasn't possible, but neither Ellwood nor Ackley was a physicist. They simply didn't know. It was a WAG. (wild assed guess).
There used to be a sign at Epps store comparing the 303 British and the 303 Epps. Ellwood claimed that a 180 gr bullet shot from the 303 Epps Improved was traveling at 2900 fps vs 2440 fps for the 303 British. That's about a 19% boost in velocity. Of course, that wasn't the case, but because chronographs were not common then, his estimates were based on some very liberal interpretations and common beliefs of the day. He sold a lot of rifles to guys expecting 2900 fps from their rifles. It wasn't dishonest. He thought he was right.
In his defense, he might have been using a P14 for his tests, that could handle more pressure than a Lee Enfield. If he loaded a powder like 4320 or 3031 in a 303 Epps, he could have safely managed 2800 fps and maybe a wee bit more, but again, he would have had no way of verifying that.
I believe that both men talked about having some of their loads chronoed, but I do not recall where I read that.
So, I believe that Ackley's velocities were like Ellwood's. WAGs
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