9mm through longer than typical pistol barrels?

[peacebutready]

There are the PCCs out there that shoot 9mm. I think they typically have 16" barrels. Does a 16" barrel provide more velocity for the 9mm cartridge than a shorter barrel?

What is the best barrel length for the highest 9mm velocity?

Assume factory loaded ammo.

 

[fxvr5]

BBTI - Ballistics by the Inch :: 9mm Luger Results

(statement of intent)

www.ballisticsbytheinch.com

 

[hso]

Yep, all you have to do is search 9mm velocity vs. barrel length.

 

[Hugger-4641]

As you'll notice from HSO's chart, there's not a definite answer. This is probably dependent on the powder, charge wt, and bullet that was used in a given ammo. A slower burning powder is going to make more use of a longer barrel. A fast powder like TiteGroup probably doesn't see much advantage after 12" .

 

[peacebutready]

As you'll notice from HSO's chart, there's not a definite answer. This is probably dependent on the powder, charge wt, and bullet that was used in a given ammo. A slower burning powder is going to make more use of a longer barrel. A fast powder like TiteGroup probably doesn't see much advantage after 12" .

Yes, it depends on the powder being used. I'm guessing manufacturers use fast burning powders for 9mm due to most of it being fired through pistols.

 

[Hugger-4641]

I'm guessing manufacturers use fast burning powders for 9mm due to most of it being fired through pistols

Well, this is also subjective. HS-6 and Titegroup are both fast powders compared to rifle powders, but Titegroup is faster and cleaner. One mfg may use Titegroup or similar mixture while another may not. These choices are often made for economic reasons and not performance. If you are a mfg that produces various calibers, it might make more sense to use one powder formula that works in several calibers, but may not be "the best" in all of them.

 

[NIGHTLORD40K]

VERY generally speaking, you will see the best 9mm velocities in barrels between 9-12". Most loads peak or actually start slowing down a bit after that, but are still faster than from a 5" pistol barrel.

Military/ police SMG barrels are almost all in this length range, and not just for the sake of portability.

Civilian PCCs have to stay above 16" for legal reasons, not technical requirements.

As others have said, there no blanket answer- depends on the ammo.

If you don't have a 9mm rifle yet, get one. They are a cheap hoot to shoot!

 

[bangswitch]

Pistol ammo doesn't get as much of an increase in velocity through carbine and rifle length barrels as rifle ammo does because the powders used are optimized for short barrels (typical pistol length). You could conceivably use a rifle powder to reload 9mm or other handgun calibers to get a bigger velocity increase, but they would be totally unsuitable to use in a standard pistol. If I load my .45 Colt ammo to the safe maximum for my two handguns that use it (S&W M25-5 and Uberti SAA), I get around 900 fps on them, but still only get maybe 1250 fps in my Henry rifle with a 20" barrel.

 

[12Bravo20]

I built an AR 9mm pistol Colt SMG clone a few years ago and it has a 10.5" barrel. It does well with factory ammo and my reloads. I decided that I didn't want to mess with registering it as a SBR so I pinned and welded an extended XM177 style flash hider to get the barrel length to 16" leaving the actual barrel itself at 10.5' (rifled portion). The pistol had an arm brace installed and I didn't like shooting it with just a bare buffer tube.

 

[Jim Watson]

I get around 900 fps on them, but still only get maybe 1250 fps in my Henry rifle

Only? That is a 38% increase in velocity, a 92% increase in energy.

I see, hear, and read of three types of PCC shooter.
No 1 shoots econoball, he just wants the gun to work and the bullet to hit the target.
No 2 buys or loads to suit the longer barrel, more power ugh, ugh.
No 3 is a USPSA or IDPA competitor, he wants to just make the required power factor to keep recoil down.

 

[hso]

there's not a definite answer

But there is a clear indication that after 17" you can start to reduce velocity and that after 10-12 inches you don't gain much effective velocity with the tested ammunition.

 

[Y-T71]

The 9mm simply doesn't have the case capacity to pack enough slow burning powder into it to take advantage of a longer barrel.

 

[bangswitch]

Only? That is a 38% increase in velocity, a 92% increase in energy.

I never thought about it quite like that. I guess I should have included that I get about 75 fps more MV (verified on chrono) with the SAA (5-1/2" barrel) than I do with my M25-5 (4" barrel), so I was expecting a bigger difference with the 20" rifle. No matter really, I'm happy with what I'm getting and accuracy on all three are good. I rarely shoot the rifle past 100 yards, and at even 50 yards I can see the bullet just before it hits the target when the light is just right. I don't have to hold over very much between 50 and 100 yards. The two handguns stay within 50 yards and usually at 25 yards.

 

[LiveLife]

The 9mm simply doesn't have the case capacity to pack enough slow burning powder into it to take advantage of a longer barrel.

USPSA 9mm Major shooters pushing 124 gr bullets over 1400 fps out of 9mm pistol barrels may disagree - https://americanhandgunner.com/discover/whats-9-major/


These are chrono number differences from 4.49" 9mm pistol barrel vs 16"/17" 9mm carbine barrel where gain of 150-200+ fps was obtained from max "pistol load data powder charges":

Pistol (Glock 22/KKM 40-9mm conversion barrel) - https://www.thehighroad.org/index.p...workup-using-imr-target.921622/#post-12684310

• 115 gr RMR FMJ 4.5-4.6 gr IMR Target @1.130" : 1162-1166-1138-1110-1151 fps

Carbine (16" PSA carbine / 17" Just Right carbine) where 4.8 gr W231/HP-38 load is my 9mm reference load comparable to Winchester white box (1176 fps measured 15 ft from muzzle where I usually place my chrono to not read muzzle blast over bullet velocity) - https://www.thehighroad.org/index.p...n-9mm-40s-w-45acp.799231/page-4#post-10338994

• 115 gr Winchester FMJ 4.8 gr W231/HP-38 @ 1.135": 1315-1234-1334-1307-1296 fps (PSA)
• 115 gr RMR HM RN 5.0 gr W231/HP-38 @ 1.135: 1380-1368-1378-1387-1399 fps (JR carbine)
• 115 gr RMR HM RN 4.5-4.7 gr Promo @ 1.135": 1351-1364-1363-1357-1342 (JR carbine)

 

[Y-T71]

USPSA 9mm Major shooters pushing 124 gr bullets over 1400 fps out of 9mm pistol barrels may disagree - https://americanhandgunner.com/discover/whats-9-major/


These are chrono number differences from 4.49" 9mm pistol barrel vs 16"/17" 9mm carbine barrel where gain of 150-200+ fps was obtained from max "pistol load data powder charges":

Pistol (Glock 22/KKM 40-9mm conversion barrel) - https://www.thehighroad.org/index.p...workup-using-imr-target.921622/#post-12684310

• 115 gr RMR FMJ 4.5-4.6 gr IMR Target @1.130" : 1162-1166-1138-1110-1151 fps

Carbine (16" PSA carbine / 17" Just Right carbine) where 4.8 gr W231/HP-38 load is my 9mm reference load comparable to Winchester white box (1176 fps measured 15 ft from muzzle where I usually place my chrono to not read muzzle blast over bullet velocity) - https://www.thehighroad.org/index.p...n-9mm-40s-w-45acp.799231/page-4#post-10338994

• 115 gr Winchester FMJ 4.8 gr W231/HP-38 @ 1.135": 1315-1234-1334-1307-1296 fps (PSA)
• 115 gr RMR HM RN 5.0 gr W231/HP-38 @ 1.135: 1380-1368-1378-1387-1399 fps (JR carbine)
• 115 gr RMR HM RN 4.5-4.7 gr Promo @ 1.135": 1351-1364-1363-1357-1342 (JR carbine)

Ok, fair enough.

Guess I should have said 9mm doesn't have the case capacity to pack enough slow burning powder to take advantage of a barrel longer than ~9"-14" to realize performance gains somewhat more easily achieved in other PCC, namely larger capacity revolver cartridges, unless one is prepared to leave the reservation and use specially set up firearms loaded to much higher pressures not recognized by SAAMI or any other standards commonly accepted by commercial manufacturers of ammunition.

Can it be done? Of course.

Should it be done?

 

[LiveLife]

Guess I should have said 9mm doesn't have the case capacity to pack enough slow burning powder to take advantage of a barrel longer than ~9"-14"

Yes, that we can both agree on.

 

[luzyfuerza]

About a year ago, I switched from 45 ACP to 9mm for my carry guns. And I standardized on 124 grain HST standard pressure ammo.

When I read the OP's question, I realized that I hadn't tested velocity nor expansion of this ammo in my guns. So, I headed to my backyard today and did a little shooting.

I shot the HSTs over my chronograph and into plastic jugs filled with water to test expansion. Test guns were an SBR'd silenced CZ Scorpion EVO S3 (7 3/4" barrel)--the closest thing I have to a PCC, an XDm competition (5 1/4" barrel), and a Shield EZ (3.68" barrel). (Unfortunately, I don't have a 9mm pcc with a 16" barrel. I hope the OP will forgive me)

Here are the results:

Average velocity (STDev, number of shots)

EVO S3: 1234 fps (6.5 fps, n=7)
XDm: 1168 fps (11.4 fps, n=9)
EZ9: 1109 fps (7.8, n=9)

And this is how the bullets looked after being fired into water jugs (from left to right EVO S3, XDm and EZ9):




The bullet fired from the EVO S3 expanded to 0.783" (max diameter),
The bullet fired from the XDm expanded to 0.715",
And the bullet fired from the EZ9 expanded to 0.638".

Expansion through all three guns was significant and uniform (although, of course, this is not necessarily indicative of how it will perform in flesh after passing through fabric). The higher the velocity, the larger the recovered diameter. And even at 1234 fps, the HST bullet did not break apart.

The OP asked about best barrel length for the highest velocity from a 9mm PCC using factory ammo. My results don't really answer his question. I don't know that anyone could come up with data that would. But they do show that between 1109 and 1234 fps, HST bullet performance appears to be excellent. Certainly more than adequate for my purposes in my guns.

 

[film495]

I've seen a definite bump in velocity shooting 115 grain factory ammo in a PCC vs. same ammo in a regular full size pistol. I didn't chrono it, but the impact on steel plates was substantially greater - and looking into it, that weight seems to get the biggest bump in velocity 150 maybe 200 fps greater. when I looked into it the lighter 9mm rounds seem to be what others experienced as having the biggest increase in velocity from a carbine vs. pistol barrel. why? not a clue.

 

[Necessary_Nutrient]

If you can get Blue Dot powder, and reload jacketed bullets, you're going to see some impressive numbers! The numbers below are from an 8" barrel, I have no doubt that you'd see velocity increases beyond that length, I have a 16" but never ran the numbers. For reference, these numbers are about 170 FPS above the numbers for a Springfield XDM-9 with a 4.5" barrel, so it's bumping up fast for just a 3.5 inch barrel length jump.

7.8 Grains of Blue Dot, 124 Grain Everglades Ammo FMJ, CCI 500 Primer, 1.14 OAL got me the following out of a PSA 8" PA9:

1531
1540
1532
1516
1554
Average: 1534.6 fps
Muzzle energy: 648 Ft/Lbs

 

[Shawn Dodson]

Chronographed (Magnetospeed) velocity of a couple cartridges with my 16" bbl Ruger PC Carbine (5 rd average velocities):

124gr +P Speer Gold Dot: 1395 fps

147gr Federal HST: 1022 fps

 

[Derek Zeanah]

Chronographed (Magnetospeed) velocity of a couple cartridges with my 16" bbl Ruger PC Carbine (5 rd average velocities):

124gr +P Speer Gold Dot: 1395 fps

147gr Federal HST: 1022 fps

Interesting. I would have expected much faster than that.

 

[Walkalong]

There are the PCCs out there that shoot 9mm. I think they typically have 16" barrels. Does a 16" barrel provide more velocity for the 9mm cartridge than a shorter barrel?

What is the best barrel length for the highest 9mm velocity?

Assume factory loaded ammo.

Fast powders like N-320? No.

Medium speed like AA #5? Yes.

Slow like AA #9? A bit more still.

I have a good bit of data with 95, 115, & 124 Gr bullets in 3" to 16" barrels. But of course we don't know what powders factory ammo uses, so we'd just have to try some out.

 

[Pat Riot]

@luzyfuerza Nice test. Thank you for posting your results.
It appeared the HST’s held up well. Nice expansion across the board too.

 

[Simple Shooter]

Field test on 9mm ammo for 16” rifles

 

[peacebutready]

VERY generally speaking, you will see the best 9mm velocities in barrels between 9-12". Most loads peak or actually start slowing down a bit after that, but are still faster than from a 5" pistol barrel.

Military/ police SMG barrels are almost all in this length range, and not just for the sake of portability.

Civilian PCCs have to stay above 16" for legal reasons, not technical requirements.

As others have said, there no blanket answer- depends on the ammo.

If you don't have a 9mm rifle yet, get one. They are a cheap hoot to shoot!

I guess a person needs to apply for permission to acquire a 9mm carbine with a barrel in the 9-12" range mentioned above.