5" vs 16" 9mm barrels and velocity, better powder?

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In a 9mm rifle with a 16" barrel, 147gr factory subsonics aren't subsonic.

Comparing chrono results between a 5" barrel 9mm and a 16" barrel I'm seeing on average an 11% velocity bump. That's obviously enough to push those 147s too fast.

I've started to make some handloads for the 16" and ended up going too low, the gun cycles reliably but who wants a subsonic 9mm going only 850 fps? Gotta bump up that charge and find my 950 fps happy spot.

What I'm really wondering though is, what's a good powder to make use of all that barrel to make bullets go faster? Carrying around 16" of barrel for legal reasons and only getting a lousy 100-150 fps boost over a full sized handgun is lame.

Anyone have a load using a slower powder that works well in their carbine? This ammo would be for 'carbine only' so if it doesn't work right, produces crap velocities or massive fireballs in a handgun it doesn't matter, we just want it fast out of a 16" barrel without being +P+ or 9mm major (which seems to be what some people are doing).

Searching for the info online produces painfully bogus results (so far).
 
So you are lookin for max velocity out of a 16 inch barrel and 147??

More max velocity out of a 16" with a 115. I have good dope out to 200 yards with factory 115gr wolf @1250 fps, but I suspect it can go faster with the right load that takes advantage of the barrel.

147 subs have a speed limit out of anything (obviously).
 
I remember on the Kel Tec forum a guy had broken 2000fps out of his sub2000 with 90gr bullets and a slower powder, I think it was Longshot maybe? I tried something similar and got wild velocity variations, but it's probably because I suck at reloading, lol. I think variations in crimp had a large effect.
 
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Blue Dot is listed as a magnum powder...… but it's best at getting the most velocity out of a non magnum cartridge such as 9mm. 1400 FPS should be no problem with a 115 grain bullet from a 16 inch barrel.
Typically...… a slower burning powder will yield more velocity from a longer barrel. Hodgon has a powder burn rate chart somewhere.....

And....WSF should safely get you another 100 fps with a 147 grain bullets. My favorite 9mm load.... 3.8 grains of WSF with a 147 grain HC bullet. Around 900-925 fps with a handgun and around 975 with a carbine. That load has cycled every gun I've tried without any problems.

https://www.hodgdon.com/wp-content/uploads/2019/11/burn-rate-color.pdf
 
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I get a solid 1500fps with RMR 115fmj bullets and Power Pistol, not even a max charge (accuracy node). I got more velocity with AA#7, closer to 1600fps, but accuracy was not good. I get better than 2.5” 10 shot groups @100yds. This is with a PSA 16” upper.

I did not try a lot of powders, I was so happy with the results with Power Pistol, way better results than I had hoped for, so I just stayed with it.
 
I've had good results with VV 3N37 in various 9mm loadings although my focus now is primarily subsonic loadings. 3N37 gives a low ES and meters very very nicely.

6.0 under my cast wax lubed 125 LRN clocked 1295 FPS in a 9" MP5 clone, published max is between 6.5 and 6.7 grains with a jacketed 115.
 
We were using 7.2/V 3N38 with the 147s running 1150 in 4" BHP and just at 1200 in 5 inch 1911 guns. I never tried those in the longer barrels, so not sure what they do with barrel length.

Someone mentioned Bluedot, that is a good move for longer barrels, one could work with that, and Toprudder getting 1500 with 115s and Power Pistol is probably about as good as you are going to do with 115s.

Looking to enhance, I think I would drop weight to the 90 Raptors, or 90 Lehigh Extreme Penetrators. Currently I use 7.5/V 3N37 with 90 Lehighs and get 1605 fps in 7.5 inch guns. I don't have a 16 inch gun anymore.

9mm is hard to do much in longer guns, as mentioned you gain next to nothing with factory ammo with the longer barrels.
 
Some load results today, all out of the 16" barrel, 5 shot averages.

The subsonics:

147gr Berry's Plated w/3.7gr CFE Pistol = 950 fps
147gr Berry's Plated w/3.9gr CFE Pistol = 1002 fps

The SD on the 3.7gr load was 3. Not bad. I'll make up enough 3.6, 3.7 and 3.8gr variants to do accuracy testing next time.

The 'go real fast':

115gr Wolf factory load = 1233 fps
124gr NATO factory load = 1367 fps
90gr Speer JHP w/7.0gr Power Pistol = 1768 fps
90gr Speer JHP w/7.3gr Power Pistol = 1780 fps

The 7.3gr load produced "way more noise" according to the observer writing down the shot results.

That's not bad, no super bad pressure signs around the primer but the case mouths are beat to crap. It's just a blowback carbine so it's opening a little faster than usual?

I want to make some 115gr loads @7.0gr as well now. 7.1gr is the max charge with a 115gr, but I don't have any 115gr bullets except for some Berry's and we'll be pushing them past the speed limit. So... my crazy idea is to pull some bullets from factory Wolf 115gr and use those. Steel core bullets should stand up to the test.

I've re-used unfired pulled steel cases before, so the second half of the plan is to stick a 115gr Berry's bullet back on top of the Wolf load and run them in the G34. They'll be slow enough there.
 
Lots of people using poly coated major rounds in open guns. And they are much hotter than what you have loaded.
Tilley has been using blue bullets, for example.
 
The 'go real fast':

115gr Wolf factory load = 1233 fps
124gr NATO factory load = 1367 fps
90gr Speer JHP w/7.0gr Power Pistol = 1768 fps
90gr Speer JHP w/7.3gr Power Pistol = 1780 fps
:eek: I may have to try some 90gn bullets.

That's not bad, no super bad pressure signs around the primer but the case mouths are beat to crap. It's just a blowback carbine so it's opening a little faster than usual?
I have a Kaw Valley heavy buffer, I believe it weighs more than twice what the normal AR buffer weighs. Slows down the action some, which might help your problem. You can feel the extra weight moving when you shoot, though.

I want to make some 115gr loads @7.0gr as well now. 7.1gr is the max charge with a 115gr, but I don't have any 115gr bullets except for some Berry's and we'll be pushing them past the speed limit. So... my crazy idea is to pull some bullets from factory Wolf 115gr and use those. Steel core bullets should stand up to the test.
I use the RMR 115 FMJ, they work very well in my gun. The load data I had (I think from Alliant) was 6.7gn, so that is as high as I went.
 
N/m...I thought this was a basement thread on inch/velocity propulsion. I see now I have been mistaken
 
In a 9mm rifle with a 16" barrel, 147gr factory subsonics aren't subsonic.

Anyone have a load using a slower powder that works well in their carbine? This ammo would be for 'carbine only' so if it doesn't work right, produces crap velocities or massive fireballs in a handgun it doesn't matter, we just want it fast out of a 16" barrel without being +P+ or 9mm major (which seems to be what some people are doing).

Searching for the info online produces painfully bogus results (so far).

I wanted to make a 9mm hunting round for my PCC, and had the same result as you- even with a long barrel, wasn't getting up to target speed (1050). I ended up using an 'over Hodgdon max' (which is a hot load in any other book).

I ended up with 3.7grains of Titegroup, which yielded 1050fps and could reliably hit my 12" steel plate at 100, so I called it a success.
 
I pulled the wolf bullets tonight, powder charges were a uniform 4.8gr of whatever powder they're using. Bullets were between 114.8 and 116.5gr, so not as uniform there but good enough for the next speed test.

I reloaded the wolf cases with their powder and a berry's 115gr and loaded up the 7.0gr of Power Pistol under the wolf projectiles.

Next up I need to do the 4.6, 4.7 and 4.8gr charges of CFE Pistol under the 147s to see which is the most accurate subsonic. Probably test them at 50 yards to start. Should happen this weekend depending on actual chores getting done.

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Well that was a disaster. I setup at 50 yards, fired some speer 147gr factory to establish where the subs might hit, then proceeded to fire groups. The speer was about what I would expect from this rifle, a 3 MOA group. All of my 147gr handloads were hot garbage, like 10+ MOA. 5-6" groups with little consistency. Ugh.

Giving up on those loads, I stuffed some 115gr wolf in and hit the 150 yard gong a few times just to make myself feel better. Then I tried my hybrid wolf rounds (with the berry's 115gr bullets in them) and... was missing by 3' or so. No real recoil so it's easy to spot your hits and I was watching things go way right then way left then way high.

Maybe trying to use Berry's for accuracy at 50 and 150 yards is a just a dumb idea. Guess I need to find some actual bullets and try the loads again.
 
Currently I use 7.5/V 3N37 with 90 Lehighs and get 1605 fps in 7.5 inch guns.

I was just gifted a partial container of 3N37, and I have 90gr XTPs which they have on their load chart. They're showing a max load of 7.2gr with a velocity of 1512 fps out of a 4" gun. Going to see what that runs out of a 16" for sure.
 
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