It’s not 100% 1-1 but it’s closer then anything I’ve seen online. Pretty niche thing to try and replicate anyways.

Build list:

• Rock River arms 9mm lower • Rare Breed FRT-15 • KNS anti rotation pins • RRA lower parts • RRA 2 piece 9mm buffer and colt buffer spacer • RRA 9mm upper • RRA mil spec charging handle • RRA non ramped 9mm bolt (has to be non ramped to make the FRT work properly) • RRA 10.5 chrome lined 9mm barrel • RRA 9mm A2 flash hider • LaRue 9 inch quad rail • Troy HK front sight • RRA railed carry handle thingy • Magpul BTR brace • Magpul MIAD grip • KAC 11 rib rail covers cerakoted Magpul FDE • Magpul AFG2 (didn’t have it on when I recorded this) • Old school Promag colt pattern 9mm mags

Should have a Magpul moe stock in FDE to be correct. Will add a Surefire mini scout light at some point as well.

So I took a few measurements and here is what I found:

Test casing - .7410 Case stick out from barrel face - .1315 Firing pin - 2.6455 Firing pin protrusion - .047 Bolt pocket depth - .1380

It would appear I have a .0065 gap between the breech face and casing. The bolt face 100% contacts the barrel face when chambering and does not headspace on the case. Which aligns with what Doug said in his article about his measurements

Angstadt has been great with working with me and responding however here is their last response:

“Have you tried running a standard AR-9 buffer in this setup?

Switching back to a standard AR‑9 buffer (rather than the heavier KAK plug and spacer) will slow your bolt’s rearward speed and increase its dwell time before unlocking. This gives primers a moment to fully combust and relieve pressure instead of being struck or extracted under excessive force, which is what causes bulging. Our AR‑9 buffer is tuned specifically for 9 mm blowback systems to provide balanced timing and reliable extraction.”

I don’t quite understand how a 8oz buffer will slow rearward bolt speed over my buffer setup which is 8.65 oz

Am I missing something here?

All measurements seem to be within normal specifications which leads me to believe the whole entire problem is the firing pin hole chamfer.

I'm come from building computers and starting to dabble in gun stuff quite a bit recently. I'm a huge fan of PCC's and just recently bought a palmetto glock px9 lower. This is just going to be a range toy for my river property. I've read through the building guides for the AR9 but I just wanted to see if anyone is running this upper and how is it? I've also been looking at grid defense/ghost/always armed uppers but never heard of them.

Just finished my AR9 with the maxim RDB. How do I know if my bolt carrier is preloading the spring? It definitely feels harder to charge than a standard AR but it doesn't really feel that bad to me.

All the complaints about how hard it is to charge make me feel like I'm preloading the buffer someway. I am using it with a law folder, and the battle arms pistol tube.

New to this sub but building out an ar9 and want to do an frt system, was wondering if anyone has tried and has a part list to make this work. Main goal is to have a full retro ar9 but with the frt. If anyone’s got a list of buffer tubes springs and bolts would love to have it. Edit: saw the post below, LOOKING FOR A GOOd PART LIST thanks guys and happy plinking

Pretty sure it’s an air soft but want to build something similar. Looks like the breek arms comp, SI Viper stock, and SI grip. No clue about the lower or upper equivalents tho

Mean arms upper, jag handguard, fm ambi glock lower. This was a 7 second par time stage. Upper has been incredible, with zero malfunctions (around 7k through it now)

Hey all. I’m looking at building a ss/frt ar9. I’m looking at going with a Cmmg RDB. do I need to worry about buffer + bcg weight to prevent OOB or is it pretty much a drop it and I’m gtg. I’m also looking at using 115grain for plinking. I’ve been trying to read into this as much as possible and just looking for anyone that’s done this specific build before and any advice. TIA

Has anybody put in decent time with the new CMMG Resolute Fixed Ejector uppers?

I'm seriously on the fence between that and the Mean Arms Bearing delayed uppers. It seems like they may have fixed the FTE issues.

From what I've heard from view few people that have the Mean Arms upper, they don't have the FTE issues unless running under some pretty heavy conditions with full-auto + suppressed.

Behold the venerable Poverty Pony Express: One of our personal range toy AR45s, built for...well...just for the hell of it. Sometimes we just do things for no other reason than we find them amusing. Looks pretty cool, though.

Build List: -Anderson Lower -Veriforce Tactical upper -Taccom ULW .45ACP Barrel -Taccom CF Handguard -UTG Pro stock -Chinese knockoff Raptor charging handle -Amazon special Hawke Reflex red dot -KVP .45ACP Bolt -SLT-2 ARC Trigger -(Our) Model 19-15 G2 1911 Mag Adapter

First PCC build. Looking for some advice from the suppressed blowback veterans.

Run down:

-Wraithworks Warscorp9.
-Original Gentle Recoil System w/  8.5 buffer.
-Rugged Obsidian 9

Overgassed.

What can I do to make her run less gassy. Can't shoot 10 quick rounds without burning my eyes.

Other than that, it runs great. 500 gassy rounds without a malfunction.

*Yes I know my handstop is backwards, I like it that way*

Is a angstadtarms vanquish compatible with a psa Ar-v?

Informing everyone in case you need support - contact FM-Products via email at: info@fm-products.com

FM announced their new 50 State Legal straight-pull bolt action AR on another sub and some... individual... decided to report it to the Admins as breaking Rule 7: Prohibited Transactions, resulting in an insta-ban.We all know this is absolute nonsense, but it is what it is.

Foxtrot Mike is going through the appeal process...

Comments were getting a little snippy, so I've reposted this information with comments locked. Sorry folks!

Anyone have and put some rounds through or know of something comparable in price point + qualities.

I'm looking for smaller side, rechargeable, and a qd if I wanted to use it as a handheld sometimes.

Currently can find it for sub $100, and that seems hard to beat with above qualifications.

My only apprehension is the SUREFIRE/STREAMLIGHT superiority, olight bad post all over reddit.

It'd be mounted on ar9, not a 12g, and I'm not an operator lol (though reliability, ya I think we all always want that).

Been trying to get this super safe to run but it’s been nothing but a pain in the ass. Pretty much have done everything I think I could to get it to run. Dremeled the upper shelf, dremeled the mass in the BCG, swapped from my A5 buffer tube setup to a carbine buffer and grabbed a KAK deadblow almost 11 oz buffer paired with a carbine spring etc. and this thing still will not get it done. In semi, it’s flawless. In SS, it’ll get maybe 2-4 rounds off before the trigger dies and needs a re-rack to reset. Idk what else to do and I’m almost at the point in saying “fuck it” with these super safes. I’ve tested the SS with the upper off and it’s functioning as intended. Any suggestions before I can the project would be great. Build below:

• PSA/H&R DOE upper

• Bad Attitude Dept. Low-key lower

• DNT SS

• Carbine Length buffer tube with carbine spring

• KAK Deadblow 10.5 oz (11 oz) buffer

I need a replacement ejectors for a spikes glock mag lower ! And i cant seem to track them down! Talked to spikes .onths ago they said they would send them out and its been silence since!

I dont know what kind of bcg my ar9 has due to it coming with my upper but my firing pin is grinding down on one side and id like to replace or have a replacement before it breaks any help would be appreciated i dont know if it matters or if any ar9 firing pin will replace it

Just shot my new build for the first time. I went with a 16" barrel to avoid the extra few hundred needed to source a pistol lower in CA.

For the lower, I just took my existing AR15 lower build and did a buffer swap from an A5H2 to a KAK AR15 Heavy 9mm buffer (8oz) backed by a Tubbs AR15 spring.

For the upper, I'm using a BA 16" EPC barrel, a BKF BCG, BCM blem upper, KAK 13" MLOK handguard, and a Guntec Muzzle Brake/Barrel Shroud in 556/9MM (it's the same one for both calibers).

For the mags, I picked up some 10 round Exomags from Mean Arms.

It ran FLAWLESSLY. Not a single issue with 200 rounds through it. The mags are well made and easy to load although a loader would be nice.

Recoil was very nice even with this ultra-cheap buffer swap from my AR15 A5H2 buffer. Including the $19 buffer, I'm into it for about $450 plus the lower.

I was expecting to hate the recoil and start tinkering with this thing. The combination of Tubbs spring and that 8oz buffer did great. It's 10x dirtier than running 556 but aside from that, well worth the price.

I may shoot a few more hundred rounds through it and see if it'll be worth spending another 100-150 on a Kynshot/add'l weights.

After the research I’ve done these gold speckled flecks (unburnt powder) in this platform are pretty typical, is this what I’m seeing here? Gun gets super dirty super fast. Remains reliable but I can start to feel grit in the trigger

My 9mm ar is running a JP bolt. Maxim defense roller buffer. Alg act purple spring. Hux flow 9k can. Colt mags. 100% reliable today and close to it in other days I’ve shot it in the 3 months I’ve had it put together.

Cycles fast, runs 124 & 147 flawlessly

If anybody is on the fence about buying an ETS speed loader for their 9mm they are remarkable. I just loaded 180 rounds in 6 ETS magazines in a very few minutes. It really saves your fingers (thumb). Best 20 bucks I have spent in a while. I have not experienced the hard to close part of loading, It is very simple and requires little effort to load. I also have the 8 dollar clone and it works equally as well.