those military weapons are all sub machine guns, small, lightweight guns that spit a lot of lead very quickly. I however like the pistol cal carbine as a self defense/home defense round. it does not over penetrate, it's not nearly as loud as the usual suspect home defense calibers, and it's still lethal and accurate for just about any range that is defensible in court.
why so many don't use them? I haven't a clue. my list of home defense weapons in order of which I would grab first is
1. handgun: quick to load, quick to acquire target, compact and easy to move around corners. does not penetrate walls as easily as rifle cartridges
2. pistol cal carbine: not as easy to move around corners and increases both noise and velocity but still under heavy penetration levels.
3. standard carbine: last thing I would want to grab.
I don't follow the chain of thought that says your best option is a shotgun loaded with 00. I am fighting to protect my property and family, why would I want a gun that fires multiple projectiles at once in multiple directions and destroy my own stuff and possibly a loved one?
for survival situations or self defense outside the home however I would leave the 9mm at home and grab the 223 instead, more lethal and more accurate over range.
all guns lost in a tragic smelting accident.
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