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[burger and fries]

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[paul0660]

I dunno.

http://gunnuts.net/2009/04/03/9mm-nato-vs-9mm-luger/

[CSDGuy]

9mm NATO rounds are loaded a little hotter than a standard 9mm that's loaded to SAAMI spec. Basically, it's a +P load... so yeah, it'll kick a little bit more than a commercial, non +P load.

[norcal01]

I was the unit armorer for six of my 9 years in the army and I noticed that most of the M9's in my arms room were used so heavily that the recoil springs were slightly shorter than the one in my personal 92. Maybe it's just me but it seemed like whenever I changed a spring out on an M9 at the range it felt like the recoil was a little less, or at least the muzzle seemed to flip less. As far as ammo, CSDGuy is correct, the NATO rounds are a little hotter than civilian.