AR9 Build

[bnicks23]

I am looking to build an AR9 SBR. Seems little different than a AR15 part wise. I want to know what ill need,what i am missing for parts, and what places actually have items in stock. I have a buffer tube and m4 butt-stock from my rifle already (not milspec and unsure if can be used with 9mm) This is what i got so far.

Rail - unsure what kind
Flash Can - unsure what kind
Trigger Group - unsure what kind

Lower Receiver - https://www.joeboboutfitters.com/Sp...ine_Compatible_Billet_Lower_p/jb-spartan9.htm
Upper Receiver - https://www.rainierarms.com/rainier-arms-forged-mil-spec-upper-minus-fa-22-lr
Bolt -

https://www.rainierarms.com/quarter-circle-10-9mm-glock-cut-bolt-assembly

Barrel - https://www.rainierarms.com/quarter-circle-10-barrels-9mm

 

[Shawnyc]

Only difference is you need a 9mm upper with a 9mm ramped bolt, and a mag block for mags assuming your using a standard receiver.

 

[bnicks23]

Only difference is you need a 9mm upper with a 9mm ramped bolt, and a mag block for mags assuming your using a standard receiver.

Won't I need a different buffer and buffer spring? And I am looking to make a dedicated lower as well.

 

[Shawnyc]

If you live in MA and want a dedicated lower your limited to private sales. I'm pretty sure lots of folks run standard buffers. They do make 9mm ones if you have reliability issues.

 

[wmass]

I run a standard carbine spring and buffer in my Lonewolf. A few thousand rounds without issue.

 

[ScottS]

Won't I need a different buffer and buffer spring? And I am looking to make a dedicated lower as well.

Yes. Most 9mm AR carbines run heavier and longer buffers. Heavier, because the weapon is blow-back, and the bolt is a honkin' mass coming back, and longer in order to retard the rearward travel of the bolt, as the 9mm cartridge is shorter. Letting the bolt travel too far back is hard on the bolt catch, and broken bolt catches can be a common complaint in 9mm carbines. A couple of companies make drop-in Delrin spacers you can put behind a standard-length buffer, and some people drop quarters into the buffer tube to act as a spacer. I use the Spikes ST-9X buffer on both of mine, which is both heavier and longer, but there are others out there.

There's a school of thought that argues for using heavier (AR10) buffer springs which have a higher initial weight (the force against the bolt in the forward position) in order to slow/dampen the blow-back bolt. I use normal weight (albeit flat-wire) carbine springs.

9mm AR's are the bomb. Amazingly fun to shoot.

 

[bnicks23]

Yes. Most 9mm AR carbines run heavier and longer buffers. Heavier, because the weapon is blow-back, and the bolt is a honkin' mass coming back, and longer in order to retard the rearward travel of the bolt, as the 9mm cartridge is shorter. Letting the bolt travel too far back is hard on the bolt catch, and broken bolt catches can be a common complaint in 9mm carbines. A couple of companies make drop-in Delrin spacers you can put behind a standard-length buffer, and some people drop quarters into the buffer tube to act as a spacer. I use the Spikes ST-9X buffer on both of mine, which is both heavier and longer, but there are others out there.

There's a school of thought that argues for using heavier (AR10) buffer springs which have a higher initial weight (the force against the bolt in the forward position) in order to slow/dampen the blow-back bolt. I use normal weight (albeit flat-wire) carbine springs.

9mm AR's are the bomb. Amazingly fun to shoot.

Those ARs look awesome. Exactly what i am looking to do but with a dedicated 9mm upper receiver where i don't need to make the extraction port smaller. What lower receiver did you use for the bottom left? The spikes buffer seems to be out of stock everywhere. The only one similar to it would be the Kaw Valley Precision Solid Stainless Steel Blowback Buffer - 7.5oz. Its an oz lighter than the spikes, would that make a huge difference?

 

[boilermaker]

Those ARs look awesome. Exactly what i am looking to do but with a dedicated 9mm upper receiver where i don't need to make the extraction port smaller. What lower receiver did you use for the bottom right? The spikes buffer seems to be out of stock everywhere. The only one similar to it would be the Kaw Valley Precision Solid Stainless Steel Blowback Buffer - 7.5oz. Its an oz lighter than the spikes, would that make a huge difference?

That lower looks like an Aero Precision lower, given the "A" on the magwell. Could be wrong though

 

[ScottS]

Those ARs look awesome. Exactly what i am looking to do but with a dedicated 9mm upper receiver where i don't need to make the extraction port smaller. What lower receiver did you use for the bottom left? The spikes buffer seems to be out of stock everywhere. The only one similar to it would be the Kaw Valley Precision Solid Stainless Steel Blowback Buffer - 7.5oz. Its an oz lighter than the spikes, would that make a huge difference?

The Glock-compatible lower on the left is the Runner Runner Guns R9, but it's the same lower sold by New Frontier Armory as the C9 and I think it's the same as the Spartan-9 from Joe Bob's Outfitters. Nice billet lower, and an easy build. I went with a "traditional" 9mm upper (gas deflector, no brass deflector, 1/2 ejection port cover) because that's what Colt originally put on their 9mm SMGs. Kind of a nod to tradition. Kaw Valley Precision 8.5" barrel and a 1/2"-36 flash hider.

I noticed 9mmAR.com has Spike's buffer in stock here.

My Colt-compatible in the upper right is an Aero Precision lower as boilermaker Spock'd out with a PSA drop-in magwell conversion. Here it is with the suppressed upper:

Both guns run like little sewing machines.

Let me know if there's anything I can help with.

 

[bnicks23]

The Glock-compatible lower on the left is the Runner Runner Guns R9, but it's the same lower sold by New Frontier Armory as the C9 and I think it's the same as the Spartan-9 from Joe Bob's Outfitters. Nice billet lower, and an easy build. I went with a "traditional" 9mm upper (gas deflector, no brass deflector, 1/2 ejection port cover) because that's what Colt originally put on their 9mm SMGs. Kind of a nod to tradition. Kaw Valley Precision 8.5" barrel and a 1/2"-36 flash hider.

I noticed 9mmAR.com has Spike's buffer in stock here.

My Colt-compatible in the upper right is an Aero Precision lower as boilermaker Spock'd out with a PSA drop-in magwell conversion. Here it is with the suppressed upper:

Both guns run like little sewing machines.

Let me know if there's anything I can help with.

I found this for a spring to run with the spikes buffer. Does this seem like a decent spring to use?
http://www.opticsplanet.com/strike-industries-ar-carbine-flat-wire-spring.html

This is what i got so far for parts:

Lower - https://newfrontierarmory.com/shop/c-9-stripped-billet-lower-receiver-glock-style-mags/
Upper - https://www.rainierarms.com/rainier-arms-forged-mil-spec-upper-minus-fa-22-lr
Bolt - https://www.rainierarms.com/quarter-circle-10-9mm-glock-cut-bolt-assembly
Barrel (10.5) - https://www.rainierarms.com/quarter-circle-10-barrels-9mm
Buffer - http://stores.9mmar.com/spikes-tactical-st-9x-heavy-buffer/
Rail - probably going to be a 12" (unsure what kind yet)
Flash can - Unsure still
trigger group - Unsure still
Already have non-milspec m4 stock with tube

Unsure where to get a 9mm feed ramp or does it not need one because of the glock mag being there? I have no idea.

 

[Shawnyc]

My Colt-compatible in the upper right is an Aero Precision lower as boilermaker Spock'd out with a PSA drop-in magwell conversion. Here it is with the suppressed upper:

Both guns run like little sewing machines.

Let me know if there's anything I can help with.

Can you link to the PSA MAGwell conversion? Thanks!

 

[ScottS]

I found this for a spring to run with the spikes buffer. Does this seem like a decent spring to use?
http://www.opticsplanet.com/strike-industries-ar-carbine-flat-wire-spring.html

This is what i got so far for parts:

Lower - https://newfrontierarmory.com/shop/c-9-stripped-billet-lower-receiver-glock-style-mags/
Upper - https://www.rainierarms.com/rainier-arms-forged-mil-spec-upper-minus-fa-22-lr
Bolt - https://www.rainierarms.com/quarter-circle-10-9mm-glock-cut-bolt-assembly
Barrel (10.5) - https://www.rainierarms.com/quarter-circle-10-barrels-9mm
Buffer - http://stores.9mmar.com/spikes-tactical-st-9x-heavy-buffer/
Rail - probably going to be a 12" (unsure what kind yet)
Flash can - Unsure still
trigger group - Unsure still
Already have non-milspec m4 stock with tube

Unsure where to get a 9mm feed ramp. i have seen some on the lower and some on the upper but both are stripped and if i am missing anything let me know

The parts all look right, although a couple of the parts are what my Midwestern mother calls "spendy."

The Rainier upper is really just a slick-side upper. Anderson, PSA, and Aero Precision all make slick-slide uppers for between $60-$75. (AIM had the Anderson ones for $40, but I don't know if they're still in stock.)

Quarter Circle certainly makes good stuff, but you can get Kaw Valley Precision (Joe Bob's) or Faxxon (Brownells) barrels for a lot less with no loss in quality. BTW, you don't really gain or lose anything, velocity-wise between 8.5" and 10.5", but the shorter barrel handles better, IMO. When you get a rail, remember that 9mm barrels measure differently because there's no barrel extension (like on an AR), so the standard rail-to-barrel length used in AR15 is a bit off. I;d fit my barrel and measure it before I ordered a rail.

No need to buy a separate 9mm feed ramp. It's integral to the lower/magazine combo. You see them built into the front of Colt-style conversion because the Colt magazine goes straight in, farther back from the chamber. There needs to be something to "fill that gap."

You can kind of see the Glock setup here:

 

[ruebarb]

Here is mine

https://youtu.be/j4k6a-z0HiU

https://youtu.be/cBg-uWGeBOA

You can get alot of the parts from https://www.joeboboutfitters.com/Default.asp

Spartan Upper and lower
Kaw Valley BCG
Kaw Valley Comp
kaw Valey 8.5 barrel
Ar 9 Heavy buffer and Spring
Law Tactical folding stock adapter
Dolos Barrel release, comes with a decent handguard now, vs the POS it previously came with, https://www.coppercustom.com/product-tag/dolos/
YHM handguard - Compatible with the thread on the Dolos, Used a 9", they also have a 7" http://yhm.net/accessories/forearms/mlok-handguards.html
mission first minimalist stock
ALG milspec trigger, moddifed by me
Ergo AR grip
Vortex Sparc AR red dot
Seekins Precision Bolt catch
Bad-Ass Ambi safety selector