The Firing Line Forums

Go Back   The Firing Line Forums > Hogan's Alley > Handguns: The Semi-automatic Forum

Reply
 
Thread Tools Search this Thread
Old December 8, 2012, 03:38 PM   #1
FlySubCompact
Senior Member
 
Join Date: February 16, 2012
Posts: 306
A shorter barrel....most efficient defense rounds

I have a G23 and a G27. Both are stock .40sw caliber, but I also have 9mm conversion barrels for them.

I know that the longer barrel of the G23 will push the bullet faster from the muzzle than the G27. I've seen this on Youtube with folks shooting through chronographs. A tad longer barrel will give more FPS because the expanding gases have more distance to work on speeding the bullet.

What I'd like to know is if ammo can be custom taylored to be used more efficently in guns with compact barrels?

I also wonder if different wieght bullets are better suited for short barrel pistols. Like maybe a 124gr 9mm would be more efficient in a in a G26 or a 147 gr would work better in a G19, or vice versa.
FlySubCompact is offline  
Old December 8, 2012, 06:04 PM   #2
RC20
Senior Member
 
Join Date: April 10, 2008
Location: Alaska
Posts: 7,014
Pretty much no and no.

Contention is that the 124s are better than 147s, doesn't matter what the barrel is the relationship stays the same (velocity vs weight). Until you shoot a live human being (or do a post in depth) you will never know for sure.

Just make sure its a known brand SD ammo and you have done the best you can. No guarantees until you get up to 75mm or so.

You still have to keep the pressure below max and that occurs early in the firing cycle.

There are some rifle powders that allow a steadier constant pressure that stays below max, but a pistol is too short.

Pick 124, 147 or mix them if you want and hope for the best.
RC20 is offline  
Old December 8, 2012, 06:48 PM   #3
Brian Pfleuger
Moderator Emeritus
 
Join Date: June 25, 2008
Location: Austin, CO
Posts: 19,578
Ammo can absolutely be tailored to shorter barrels.

The faster the powder, the faster the bullet accelerates early in the barrel.

There are variables and complexities, but you can certainly build ammo better suited for longer or short barrels.

There's usually not much you can do to make changes with "similar" barrel lengths. The powder that produces the best velocity in a 5" barrel will probably also be best in a 4" barrel but when you start getting more dramatic difference, like 8" versus 3", more can be done.

You can also make changes that might not change the velocity but might reduce muzzle blast and flash.
Brian Pfleuger is offline  
Old December 8, 2012, 07:37 PM   #4
jmr40
Senior Member
 
Join Date: June 15, 2008
Location: Georgia
Posts: 10,792
The difference between a G27, G23, and even a G22 is pretty insignificant really. I think you're over thinking this a bit. Whatever load gives you the fastest speeds with a G22 will also be the fastest with the other 2.

This is really more of an issue when comparing revolvers with 6-8" barrels with 2-3" barrels. Even then the same loads that are fastest with the long barrels will be faster in the shorter barrels.

Probably the best advice is to note that heavier bullets will probably be more effective if you have to shoot a shorter barreled gun. In 357 revolvers a 125 gr bullet running 1400-1500 fps is pretty effective, but that bullet weight is far less effective a 38 special speeds from 2-3" barrels. The traditional 158 gr bullets are a better choice here since they rely less on speed to get their performance.
jmr40 is offline  
Old December 9, 2012, 01:04 AM   #5
FlySubCompact
Senior Member
 
Join Date: February 16, 2012
Posts: 306
I may be overthinking this......or trying to implant a reason in my subconscience so I can justify forking out even more money on a chrono to go with all my new reloading stuff.
FlySubCompact is offline  
Old December 9, 2012, 04:37 AM   #6
Rifleman1952
Senior Member
 
Join Date: September 1, 2012
Location: Ohio
Posts: 284
Check out Speer's Short Barrel line. It's my understanding that the problem with shooting, say a .38 special, out of a 2" barrel, is that the round just isn't going fast enough to cause a hollow point bullet to reliably expand on impact. From the testing I've seen, Speer seems to have solved that problem with their 135 gr .38 +P rounds from their Short Barrel line. Speer also offers other standard handgun calibers designed for concealed carry type handguns with shorter barrels. Speer is what I use now in my S&W Model 60.

Last edited by Rifleman1952; December 9, 2012 at 04:46 AM.
Rifleman1952 is offline  
Old December 9, 2012, 10:29 AM   #7
Brian Pfleuger
Moderator Emeritus
 
Join Date: June 25, 2008
Location: Austin, CO
Posts: 19,578
There are things to consider other than pure speed too, such as flash and recoil generated by muzzle pressure.

For instance, QuickLoad thinks that Power Pistol would generate the most MV using a 155gr Hornady XTP in a 40SW with a 5" barrel, at about 1,309fps. The muzzle pressure with that load is 5,028psi

Unique will get you within 30fps of that speed but the muzzle pressure is only 4,166psi, 18% lower.

The Power Pistol load generates 10.02 ft/lbs recoil, while the Unique load generates 8.91 ft/lbs, about 11% less.


Stepping back to a 3.5" barrel, the order of powder and velocity is unchanged among the top 3, but if you're willing to accept a 50fps drop, you can decrease muzzle pressure from Power Pistols 7,600psi to VVH N330 5,588psi, a 27% drop.

The PP load generates 8.61 ft/lbs recoil while the N330 load generates 7.37 ft/lbs, a 15% decrease.
__________________
Nobody plans to screw up their lives...
...they just don't plan not to.
-Andy Stanley
Brian Pfleuger is offline  
Old December 10, 2012, 12:34 AM   #8
stormyone
Senior Member
 
Join Date: August 30, 2005
Location: midwest
Posts: 532
There is an article, several years old, and some guys from Speer recommend the 147 gr. or 124 +P for short barrel 9mm's. This was before they started making the short barrel ammo, I believe.
stormyone is offline  
Old December 10, 2012, 12:31 PM   #9
mavracer
Senior Member
 
Join Date: February 27, 2008
Location: midwest
Posts: 4,209
"In theory, practice and theory are the same, in practice they ain't." Yogi Berra.
In theory you should lose about 50-75 fps from 23 to 27 but I've seen instances where a particular shorter barreled gun would consistantly out perform a longer barreled one.
Without a chronograph best you can do is guess. Of Course even with a chronograph yor still guessing on what'll work.
__________________
rather be judged by 12 than carried by 6
Quote:
originally posted my Mike Irwin
My handguns are are for one purpose only, though...
The starter gun on the "Fat man's mad dash tactical retreat."
mavracer is offline  
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 04:31 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2021 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Page generated in 0.07270 seconds with 10 queries