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mapsjanhere
August 17, 2011, 10:59 AM
One of my last range outings, we had two people shooting their ccw guns - an old Walther PPK in 380 ACP vs. what I think was a Ruger LC9. Both guns are pretty much identical in weight and size, so the automatic argument was performance of the 9mm vs. 380, especially from short barrels. The PPK has a 4" barrel and probably gets most of the 380's power. The Ruger only has a 3" barrel and seemed to have a rather impressive fireball. Does anyone have hard data on what is left from a 9 mm performance advantage if fired from a short barrel?

CWKahrFan
August 17, 2011, 11:22 AM
Ummmmm... The Walther PPK's barrel is 3.35" and the Ruger LC9's barrel is 3.12". I'd save some $ and go for the more powerful LC9 but they're both good guns.

jimbob86
August 17, 2011, 11:27 AM
I lost about 75-100 f/sec shooting 115 and 124 gr Hornady Custom out of my 9mm EMP (3" barrel) from what was listed on the boxes. Not sure what barrel length they did their testing in.

Daekar
August 17, 2011, 12:09 PM
One of my new favorite websites: http://www.ballisticsbytheinch.com

They have many different pistol calibers which have been chonographed out of barrels from 2" to 18" using different types of ammo. There are also muzzle-energy graphs as well. Very useful for theory-crafting IMHO.

If you're asking whether or not the 380 is better out of a short barrel than a 9mm, the answer is no. The 9mm is always going to be more powerful because of the case size.

That doesn't stop me from carrying a P238 in .380 everyday, however.

Mello2u
August 17, 2011, 12:27 PM
After looking at the posted info on http://www.ballisticsbytheinch.com,
generally speaking it seems that a 9mm 115gr bullet is fired at about the same velocities as a .380ACP 95gr bullet from similar barrel lengths such as:

.380ACP firearms
Rohrbaugh 380 2.9" barrel
Ruger LCP 2.75" barrel
Kahr P380 2.5" barrel

9mm firearms
Steyr S9 3.6" barrel
Para LDA Carry 9 3" barrel
Rohrbach R9 2.9" barrel

115 is 21% greater than 95; which does NOT mean the 115gr 9mm bullet will be 21% more effective.

mapsjanhere
August 17, 2011, 12:40 PM
Thanks for the ballisticsbytheinch links, very informative website and good data to settle these arguments. And I realized I mixed up the PP and PPK barrel lengths, I was confused how the PPK barrel was supposed to be that much longer than the Ruger with the same OAL.
As for what's the better carrying option, the smallest gun you see me running around with is usually a FN PS90, I stay out of the concealed gun debates.

kalevatom
August 17, 2011, 01:25 PM
I just chronoed some Remmington HydraShock 115gr 9mm from a Taurus 709. It's barrel length is 2.75". I was getting between 1009-1020 fps. I was wondering what others were getting from short barrels, also. Nice to see this topic come up.

jimbob86
August 17, 2011, 07:22 PM
I was wondering what others were getting from short barrels, also. Nice to see this topic come up.

As I recall, I got about 1050 out of 124 gr Hornady Custom, with my 3" barrel.

Jim Downey
August 19, 2011, 09:08 AM
Thanks for the shout-out, Daekar.

Two items I want to note - the Rohrbaugh R9 is only standard pressure 9mm, no +P.

And the Rohrbaugh R380 is *much* more pleasant to shoot. I own the R9, and a buddy has the R380 we used in the tests. If I could, I'd get a new barrel and magazine and swap down to the .380 cartridge.

Side note - we're working to get a bunch new data (the cylinder gap tests (http://ballisticsbytheinch.wordpress.com/2011/05/09/how-i-spent-my-vacation/) we did in May, and the .22 tests we did in June) all crunched and ready. We'll also be revamping the site somewhat. First news will be announced on guns.com (http://www.guns.com/), on our blog (http://ballisticsbytheinch.wordpress.com/), via twitter (http://twitter.com/#!/BBTIJim) and Facebook (http://www.facebook.com/pages/Ballistics-By-The-Inch/118222521535505), but I'm sure word will spread quickly when we 'launch' the updates.

Mello2u
August 19, 2011, 03:31 PM
Jim Downey,

Thanks for the "heads up" and the website.

Your website has lots of interesting information.

C0untZer0
August 19, 2011, 03:54 PM
If anyone ever shoots me with a .380 and I find out about it - they'll be hell to pay !

lcpiper
August 19, 2011, 04:55 PM
It' not as easy as the numbers suggest guys. I know this is not an apples to apples comparison but still, after watching these two videos you will have to admit there are some other benefits to the .380 cartridge. I am not saying it flat out makes the cartridge better but I am saying that real world it's not just about feet per second and foot pounds per inch.

http://www.youtube.com/watch?v=GGXhj1x7AqA

http://www.youtube.com/watch?v=UvnJ9RTpdT0