3” AR9 pistol

[SCARCQB]

Recently put together an AR9 pistol from parts I had. That explains the retro quad rail.

What’s interesting about this build is the 3” barrel. It keeps those standard 115 grain ball ammo subsonic. Add a suppressor and it’s quiet.

Without having to purchase subsonic ammunition. ( 125 grain fmj run at 1025 FPS )

I’m not sure about accuracy as of yet. I’ll post information on that later on.

 

[Speed3]

That's cool, let us know how accurate it is

 

[SCARCQB]

I’m using an old thread on can for now.
Waiting on fix barrel adapter for an octane 9

 

[SCARCQB]

Handguard/ rail over the barrel and suppressor. Provides some real estate to grip onto and to attach a backup sight.

 

[Bertfish]

Who makes a 3" barrel?

 

[SCARCQB]

3.1” barrel from Spinta precision.

 

[SCARCQB]

Spinta precision. On sale now for less than 50 bucks.

And it’s threaded 1/2x28

Other makers have some weird thread patterns on them. ( 1/2x36, 5/8x24) this is the first Ive seen in 1/2x28

 

[SCARCQB]

It’s not a brown recluse. But it’s suppressed enough to use indoors without hearing protection. ( I was test firing it in the basement)

 

[engineerbrian]

Cool set up. At what barrel length will you loos the ability to keep a 115 grain round sub sonic?

 

[SCARCQB]

I would say somewhere around the 4” line.

I have a 4.5” ar9 and that’s breaking the sound barrier when suppressed. ( supersonic ammo)

The 3” barrel does not.

Here a good site to get some info.

http://www.ballisticsbytheinch.com/9luger.html

 

[vgplayer]

Sweet build.

 

[05dodgedaytona]

Nice Build! What upper, lower and BCG did you use? Glock or Colt mags?

 

[gwchem]

Aww, it's so tiny and cute.

 

[cstone]

They look like Colt mags.

Have you tried 147 gr bullets? You shouldn’t have any problem keeping them subsonic and I believe that is all we ever used in the Uzi.

 

[SCARCQB]

Spinta precision barrel 3.1”
Spinta precision hybrid bolt ( 9mm, Glock/ colt compatible )
Hahn machine magwell adapter
Colt mags
10 oz buffer, AR10 recoil spring
Billet upper
Anderson virgin lower
SBA3 brace
Generic quad rail( to be replaced)

 

[05dodgedaytona]

Nice. How does it shoot?

 

[SCARCQB]

They look like Colt mags.

Have you tried 147 gr bullets? You shouldn’t have any problem keeping them subsonic and I believe that is all we ever used in the Uzi.

The 147 grain Bullets comes out at around 920 FPS. Definitely quiet.

But I wanted a subsonic platform that can use bulk Wally World ammunition.

Winchester white box or Tula. ( 115 grain fmj). Winchester forged steel cased ammo also runs around 950 FPS on a 3” barrel.

 

[SCARCQB]

4.5” AR pistol. Still breaks the sound barrier. Subsonic required to suppress efficiently.

 

[engineerbrian]

I’m still hung up on a quad rail being retro. When i think retro, i think of the old triangle hand guards

 

[SCARCQB]

Nice. How does it shoot?

I know it cycles from firing it into a bullet trap in the basement.

Accuracy wise.

I don’t know. I’ll find out soon, maybe tomorrow.

I’ll keep you guys updated.


It will look stupid when I install a 10x scope on it. Lol