More minutiae and a dose of unscientific, and maybe irrelevant bullet testing:
I picked up a box of current Underwood 147 +p hardcast and they really have changed the bullet design. -Looks- like it would be about optimum as far as bullets available in factory ammo.
They have 72% - 73% meplat, the same % as the Hunter Supply 275, pretty much a Ranch Dog hunting bullet profile. Typical 147s FP profiles are around 60%, or even a little less. A lot of handgun hunters seem to think increasing meplat that much makes big difference terminally, IDK personally, but I imagine they're going to track in a straight line as well or better than anything else out there.
They're running over 1,100 fps from my Canik, but at least one case had a -small- bulge, so they seem to be pushing pressure. Even my hottest handloads have never done that, including lots of 147s at that velocity and the 158SWCs @ 1,050 fps in the same pistol. They seem to feed just fine.
L-R 275 Hunter Supply, Underwood 147, Acme 147, Penn 147, generic fairly soft 158SWC
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For curiosity, I shot the bullets below into 6 pieces of a 2x6. They're lined up how they were found.
Gallant 147 stopped in #4. Federal 147 FMJ FP (about 1,000 fps load), Underwood 147 and 158SWC @ ~1,050 fps stopped in the 5th, in that order. Penn 147 stopped in #6. Acme 147 went through #6 and bounced off metal tank behind the wood blocks. All 147s besides the Federal load were a bit over 1,100 fps.
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I don't think that means much, if anything, beyond that all will probably work pretty similarly, with the widest meplat probably making the biggest hole on their way through.
I have read that these heavy 158+ 9mm loads tend to be faster than one might think, and have softer recoil impulse than one would think. I'm finding both of those to be true. The 158s are still in my daily carry pistol for working and walking around my place, fwiw. I'll probably get some harder, wider meplat 158SWCs and try that for the time being. Pushing those to 950, maybe 1,000 fps, would be very easy and I think would work well.