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Old 05-06-2012, 04:14 AM
WR Moore WR Moore is offline
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I'm not going to speak to expansion, I can't recall what, if any, specs the FBI test protocols had for that.

Critical Defense ammo was specifically designed for a maximum penetration of 10" in 10% ballistic gelatin, per Hornaday. This is below the FBI minimum spec of 12". While I may have differences about what penetration depth is good, a maximum of 10" leaves me a bit uneasy, especially is something like an arm is encountered before the bullet strikes the torso.

The handout Hornaday sent me on Critical Duty showed examples of greatly increased penetration capability in the same 10% ballistic gelatin. IIRC, all exemplars shown met FBI minimum penetration requirements. Expansion looked good, I didn't verify diameters against FBI specs, if any.

With modern designs, heavy clothing generally slows expansion with a corresponding increase in penetration. The fully expanded slug is generally very close to the same diameter as in bare gelatin. I noticed the 135 +P 9mm was 0.040" less in heavy clothing....no big deal.

BTW, the FBI mentions in the front of it's test protocols that agencies/end users should evaluate their own needs before looking at performance in all tests. In other words, if penetrating laminated glass or auto sheet metal isn't one of your concerns, don't worry about how the various loads performed in that test block.

I'll also point out that assuming sufficient penetration and bullet integrity to damage vital organs and structures, bullet placement is far more important than bullet diameter, velocity, construction or alleged performance in a test medium.

Last edited by WR Moore; 05-06-2012 at 04:26 AM.
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