in all the .380 ballistics tests ive seen even with highly specialized self defense ammo, they all seem to come up short on penetration.. i guess FMJ or nothing with them
9x18 makarov with the same bullets would allow expanded bullets with enough penetration to be much more effective, as makarov can be loaded safely to higher pressures than the 380, plus has a bit more case volume due to it being of a larger diameter
what i want in a pistol is 9x18 ultra, you'll probably never find it, its incredibly rare and would definitely be handload-only, but the reason i would want this in a pistol is it has all the benefits of a compact blowback pistol, but differs from say the 9x18 makarov in that it can safely run at even a bit more higher pressures, but more importantly it runs with a standard .355" bore which allows you to use all those specialized self defense expanding .380 bullets but with a velocity boost that allows you to get the expansion they offer with the necessary penetration
to make 9x18 ultra, since the 9x18 makarov is just a ruskified version of 9x18 ultra, you could probably use 9x18 brass, or 9x19 brass chopped down should suffice, ream out and load to 9x18 pressures with a .355" bullet... now if i could run something like this through a CZ-82 with a 12 shot mag with all its reliability, ergonomics, quality, and the accuracy and simplicity of a blowback, id have in my opinion the perfect everyday carry weapon.. a near future plan of mine is to rebarrel a CZ-82 to 9x18 ultra
if im not mistaken, 9x18 ultra brass can be sized in a 9mm die, and 9x18 ultra chambers can be reamed with a 9mm reamer