Pretty much any police duty rated ammo can punch through some barriers when fired out of a duty length barrel because that is an element of the design parameters. Once you get into big critter defense or the kind of hard core barrier penetration needs referenced by Mackay_Sagebrush, it’s time to go with the hard casts or solid mono-metals. Just go to Lowes or Home Depot and buy some test media for a fun day at the range.

Here’s a plain old standard pressure 124 grain Speer Gold Dot fired out a 3.7 inch barrel.



Notwithstanding those results, I keep some spare magazines loaded with Mackay's +P hard cast and with Xtreme Penetetrators for critter defense or situations requiring stout barrier penetration.

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