Waaay back, I researched as much as I could (morgue monsters v/s Jello junkies ring a bell ?)
Seemed prudent
Ayoob v/s Sanow ?
Life or death situation is very fluid - no two will ever be the same. You have to go with what YOU are comfortable with.
Is there a 100 % right answer ? NO
Is there a 100 % wrong answer ? within reason, no
If you can put 10 shots from a Ruger Mark "X" in the chest in 2 seconds, you'll prob win
My 2 cents (worth less than the price)
99% of "bad guys" will bail at the sight of a gun
Of that 1% left, 99% will curl up and cry if shot (effectively-center mass) with just about anything
The 1% left of these are the problem, drugs, booze, body armor, just plain big bad sob.
Think Miami "shoot out". Feds decided 9mm didn't cut it IN THAT SITUATION.
Most agree, 357 125g HP rules as a man stopper.
(44 doesn't dump enough energy into the body on it's way through)
Can't quite get that in a auto loader - OK, you wanna buy / carry a Coonan ? lol
Guess I shouldn't laugh, thought about it.
No, the 357 Sig uses 9mm bullets, not the same
Ammo companies messed up, build an auto cartridge around the Rem .357 125 "tulip jacket" HP.
Get it up to 1400+ f/s in a 4-5" bbl.
THAT comes under the heading of "TAKE MY MONEY !"
It's possible, I sized down some Rem tulips, played around with making them "slippery" (no, don't ask), loaded in 38 Super Comp brass. Ramped bbl. Heavy spring for caliber.
5" 1911 - 1450 f/s
And no, I have NO idea what the pressure is, It worked for me. I wouldn't suggest trying.
I LOVE to debate caliber for "whatever". SD, hunting, 1000 yd, etc.
If YOU are confident in what you use, that's the better part of the journey.
Be well my friends, weird times a commin'.