There ain't no magic bullets...to be honest any of the top offerings like Golden Sabre, Gold Dot, Federal LE9T1, etc will do fine.
^this^
Pretty much every one of the midrange defensive choices is designed to do the same things:
- penetrate to ~12-16"
- run reliably in a variety of duty pistols
- expand after going through light barriers
- keep going after somewhat heavier barriers
So it comes down to what YOU can find and test, what YOU are willing to pay for and stock in bulk, and what YOUR other guns run on, too.
Look for something you can get reliably in 50x boxes, the 20 or 25 round boxes are grossly overpriced. Beyond that, avoid anything more complicated or gimmicky than JHP or the new squishy-ball filled HP rounds, exotic ammo is generally all marketing and no performance.
That being said:
Every pistol I own** runs well on some variant of Gold Dots, and I can get them reliably from a few vendors in 50x boxes for a somewhat reasonable price. In 9x19 124grain+P runs in everything, I stock some standard pressure 124 and 115 for antiques, just because. For .45acp I stock 200 and 230 grain loads as I find them, both run fine.
I stock Winchester and Federal premium loads, too - as I find them. No reason to limit myself to one choice.
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Mike1234567, let me get this straight, you'd SELL ammo you already have to buy new ammo? Why not just set aside the old stuff as a known reliable round?
Oh, and I'll buy the old stuff at $0.20 per round, in 9x19 and .45acp
**(correction, no idea about makarov [CZ82] or tokarev [CZ52 / Yugo M57] )