barrel length for 9mm EDC

FLsh00ter

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what is the minimum barrel length to get maximum velocity out of a 9mm carry piece? such as a baby block or m&p compact or some Xd variation?
 
Interesting that one would ask that as I was just reading up on Hornady's new Critical Duty .135gr 9mm ammo. It looks absolutely great and something I have been longing for for some time now (I like hollow points but this load has a 'Flextip filled nose I like). However, they clearly state that their ballistic reports for this load which are quite impressive are taken from 'full-size' semis. Well, I carry a P11 most of the time so it makes me hesitant. As the previous poster indicated, YMMV.

-Cheers
 
barrel length for 9mm EDC

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what is the minimum barrel length to get maximum velocity out of a 9mm carry piece? such as a baby block or m&p compact or some Xd variation?


That's a free'be.

A 9.01mm.
 
Ammo manufacturers know that personal defense rounds aren't being shot out of 5" barrels. Their bullets are designed to function within a velocity range that includes 3" subcompact barrels.

Don't worry about barrel length. Buy something reliable, that you can shoot well, and that you will carry, in that order.

As a math problem for fun, to get MAXIMUM velocity, my guess would be somewhere between 15 and 20 inches. Pistol caliber carbines exhibit higher velocities than handguns. However, after a certain point, the drag created by the bullet traveling through the rifling starts to slow it down.
 
@FLsh00ter: what is the minimum barrel length to get maximum velocity out of a 9mm carry piece? such as a baby block or m&p compact or some Xd variation?

If you mean the barrel length at which the bullet stops accelerating because the rifling drag force is greater than the charge's push force, I don't know exactly, but likely more than you want in a carry gun.

This is one of the reasons "short barrel" ammo is developed, is to expand at the lower velocities developed from a shorter barrel (it's not just to tame recoil and blast). Carry gun barrels can be 2 inches for a revolver and 3 inches for a semiauto (versus 4-5 inches for a "service gun", which is more the standard most ammo is developed against).

Speer makes Gold Dot Short Barrel and Hornady makes Critical Defense (Critical Duty is made for service sized handguns). So if you want to use a short barreled gun for defense, it probably is best to use the ammo made with that in mind.
 
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AT least 12 inches. It's not a uniform amount. The most I've measured was a 200fps advantage to the 12" barrel (115gr. from 1235 in a 4" pistol to 1338fps in the12"), most are only showing 70 to 110fps increases. The little 90gr. can crack 1400fps from a 4" pistol, the same loads have managed 1500fps in the c12"...the 90gr. loads are reloads, and that powder charge used in the latest manuals has been reduced.
I stayed at the Holiday Inn Suites last night too.
 
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Random note, I read in an article/online that Hornady's new Critical Duty was developed for full-size service pistols and Critical Defense was meant to work better with short barrel carry handguns.

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Mikey Idaho

Random note, I read in an article/online that Hornady's new Critical Duty was developed for full-size service pistols and Critical Defense was meant to work better with short barrel carry handguns.

Kinda what I was referring to in post #3.

-Cheers
 
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