Comments by "GunFun ZS" (@GunFunZS) on "Q&A #11: Rockin' Like It's 1950!" video.

My theory (uneducated) for why the smaller powers had ~6.5mm cartridges was that they were closer to blank slates. Like all militaries they had elements seeking the latest tech. Most other powers had a lot of institutional groupthink that resists change. However those guys were so small, that they lacked an element who thought they needed a compromise between "old reliable" (Lot's o' power and heavy projectile) and "new tech" (controllable flat shooting, moderate recoil.) Further the longer minimum point blank range is easier to train on a smaller budget for range time.
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But they often did have civil wars. Mexico is a great example of that. Japan did a lot of empire building, and Italy had African empires. Those two would be the most iconic examples of mid caliber.
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Agreed, except for your fist sentence. .40 is considered a high pressure round, but it is not "considered +p by default." +p is a definded term, meaning that the cartridge is within official designated pressure range, that is higher than the standard designated pressure range. .40 S&W is a high pressure round whose range is standardized as such. The guns are built by default to those pressure levels. (Though some of the early flavors were engineered up from 9mm pistols and were a stretch.) However, If you are talking about those hotrod cartridges and the firearms built for them, you aren't talking about 45 ACP anymore. Much of what you said applies to 9mm Major, which can be loaded up to energy levels bordering on .357 mag, using standard 9mm brass. As with the 45ACP +P+ variants, there is a real risk of ammo mixup with common firearms which can't handle the hot ammo. Considering that there are now so many good performing cartridges in standard calibers and pressure ranges, it is hard to justify either outside of novelty or competition.
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@49:29 Ian, you shouldn't repeat this common fallacy. 40 S&W is MORE potent than 45 ACP, not less. .40 S&W is 350- 500 ft lbs ( 470 -680 J ) whereas 45 ACP is "only" in the 480-550 ft lb range for standard pressure. + P 45 acp is hotter, being in the 600-650s. I think it is a more correct statement to describe 40 as being a more compact bullet designed to do equal or greater than standard 45 ACP, than as a compromise between 45 acp and 9mm luger. It's 10 mm reduced to approximately hot 45 specs. I'm no apologist for either caliber, just for facts.
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