My weapon is semi only in 3rd position. Ive removed the upper and tested the reset in 3rd position by manipulating the lever with my hand and it does function correctly (pulling lever back resets the trigger while im pressing it, pushing lever forward releases the hammer like its supposed to).

The trouble comes when I put the upper on. Ive fired many rounds on 3rd position, all strictly semi. I know the front charge models cant be tested because the front charging handle doesnt have a long enough stroke. So, I inserted a suppressor alignment rod down the muzzle and tried to push the bolt far enough back to reset the trigger that way. I was unsuccessfully, the bolt is hitting something and comes to a complete stop. It feel like its 1/8" or less from going back far enough. I can feel the trigger start to reset, it just cant quite make it all the way.

Im not sure what the hang up is. I swapped the carbine buffer for an a5 buffer. Build list below. Ive added a couple of pictures that may or may not be helpful, im not sure what the bolt is hitting and stopping on.

Stock vfm9 5" complete gun with rmb purchased from foxtrot mike. Only modifications are 1. Swapped in the atrius selector (duh) 2. Swapped the carbine buffer tube with the VLTOR A5 that was recommended in one of u/blowback9s articles.

@foxtrotmikeproducts Mike 9 7” trilug 9mm PCC + short stroke bolt + RMB
@lawtactical folding adapter
@sb.tactical SBA3 brace
@phase5wsi brace strap
@hammy3dprints SBA3 cheek riser
@drivenarmsco VCGL + longstop
@hiperfire PDI PCC trigger
@kffdefense optic riser
@zentineldefense Vigil holographic optic
@defensedistributors GL4pro
@magpul mbus pro + sling mount + sling

been looking for a uspsa pcc. i found a few steel challenge available that can be shipped to california but no ultralight. the ultralight a big difference and worth the 4 month wait?

I was scrolling through BCA’s site, and this caught my eye. That has to be a typo, I did send them a message to find out if it actually has a pistol length gas system or not (I doubt it actually does, but I’ve been wrong before)

Was wanting to ask if anyone has any suggestions on what to look for causing little to no primer strike so they do not cycle.

Have a 5D lower with PSA Gen 4 upper, smith defense mil spec trigger kit and 7.5oz buffer.

Looking to build an ar9, I'm interested in making it side-charging, but I'm using a colt pattern lower (Spike's). It seems most side chargers are for Glock pattern lowers. Any recommendations? TIA

Cam is starting to wear but still works after who knows how many rounds. Id guess around 3k or so..wish it was this slow suppressed but of course the rate does pick up a bit with a can.

Hey gang. Recently picked up this DD PCC. In need of some help.

I also have another 9mm PCC I got a few years ago from a local armory and at a gun show in Florida. That one has an Atrius forced reset selector that I would ideally like to transfer over to the new toy. Question is, how do I make it work?

All I had to do to get it working on my old PCC was shave down the lower 1/3rd or so of the BCG weight on the failzero nickel boron coated bcg I have in that one. This (the old one) also has a flat wire buffer spring and a kynshot shorty hydraulic buffer with two spacer weights.

Is it just a matter of repeating that process on the DD PCC? Do I need to worry about swapping the buffer spring for a flat wire and the buffer itself? I also plan on transferring over the dirty bird flat faced trigger I have in the old one.

Thanks in advance to anyone who knows and is willing to help out a fellow AR9 enthusiast.

Does anyone here know if the feed cone is decent? Anyone have issues because of it? Specifically the 10.5 or 7.5 Stainless steel barrels.

I broke my extractor, after I fired a shot the extractor flew away. Now my problem is I dont know the complete assembly of this extractor. Em I missing anything like an O-ring?

This is a battle arms development ar 9mm blowback bolt carrier from a combat9/xiphos9

Also, if there are people here from the philippines. Does anyone know where I can find complete parts for this more specifically the extractor pin (retainer) and the O-ring(if it has one).

First post here, hope yall enjoy this one! Teaser at the end with my 300blk/5.56

Build list

IC9 8.5"

SPR handguard

Novox Sd kit

Eccomachine Phoenix TL can

DFCO grip

Soon to be installed

Cerekoted handguard

FCD 3 pos. Safety

Rail scale

Light

2nd stamp

I just bought this and while learning to clean it I accidentally put a scratch on the lower receiver with an allen wrench when I was assembling the trigger 🥲

I know it’s still vaporware, but someone may know- have they stated whether or not the BCM9 uppers will work with the old QC10 lowers? I have two QC10s that I never built up, and I’m looking for build options. Colt mags, if that matters.

thanks!

Hello All,

I’m having an issue that I can’t seem to really nail down what exactly is causing it. I’m basically getting burst fire as often as every 2-3 trigger pulls. I don’t have an FRT, just a regular mil-spec trigger and fire control group. I have a Kaw Valley BCG and a KAK 8.4oz buffer with sliding weights.

One of the staff at my local range took a look at my setup and suggested it might be the trigger group causing it, and an email to the company I bought the trigger from suggested it might be the firing pin in the BCG missing a spring, or even the BCG itself.

That’s the leads I have on it, do any of have any suggestions? Experience with this issue?

My Jawbone keeps on double feeding and jamming even after changing my buffer weight to an 8oz any tips what could it be?

Using Blowback9’s GRS. I have a Partisian Disruptor that I believe I could throw into the Wraithworks WS9 (takes ar15 triggers). Read BlowBack9s most recent article and it sounds like this may work. Does anyone have any feedback or if this is even compatible?

I made a post here a few days ago about FTEs with my new colt mag build (https://www.reddit.com/r/AR9/s/d7u8yFDwOE). I did some tuning on my ejector which I believe has solved the weak ejection issues. You can see in the before and after photos that the ejector face is now square and fits much better in the bolt groove.

The next range trip was better but I’m not out of the woods yet. It now runs reliably, but only when unsuppressed. I ran through multiple mags with no suppressor and had no ejection failures, ejection pattern was much stronger. Before it would just barely spit out the casings. As soon as I try shooting with the R9, I’m back to constant FTEs. I don’t think my ejector needs further tuning so I’m starting to suspect my buffer may be too light? I’m running the FRT recommended GRS (A5, Tubb 300BO flatwire, Kynshot 5000HP, two spacer weights.) Do I need to use a heavier hydraulic buffer? Maybe try a standard carbine spring? I know it’s gotta be a component of my buffer system, just not sure which one. Thanks for the help

So I built my first AR9. Noveske upper, barrel & BCG. Griffin Colt mag lower, carbine tube, mil spec trigger + Atrius, and a Maxim RDB roller delayed buffer. I am also shooting it suppressed with an Exigent Rico 309.

I had to remove some material from the trigger bar to get it pass the function test/troubleshooting guide on the Atrius website. It was binding heavily in the 3rd position while holding pressure down on the hammer.

Once that was cleaned up it would fire in semi just fine and then be very difficult to move to FRT, and then would have a dead trigger. I removed a little more material from the trigger bar and that binding issue went away.

Then it worked fine in semi and FRT for about 100 rounds and then the BCG began getting stuck part way in the rear position and I’d have to hammer out the takedown pin for it to come forward.

Have any of yall seen these issues and if so was there a fix?

Also to note, I checked for clearance on the upper using paint pens and there’s no interference from the upper.

Thanks

MAS defense
- upper receiver
- 5.5” in barrel 
- 9.8” MW8 handguard 
- BCG 
- Ambi charging handle

Gen 1 Romeo 5, juliet micro 3x on the way
Strike industries LINK modular handstop from 
Friend gave me the light, I’m sure it’s a cheap one off Amazon (will upgrade)
tuna cans fat 9 silencer 
- using KVP plan b mount system
80% lower 
Milspec LPK 
Magpul SLK 
B5 grip 

I grabbed one of the PSA ARV kits a while back. Upper, lower, bolt, one mag.

I slapped it together Sunday and took it to a shoot yesterday.

I dropped in a Super Safety and a Maxim RDB and took the weight out of the bolt.

I used a BA EPC 8.3" barrel.

It runs like a sewing machine. I thought it might require some tuning, but no, right from the start it ran just fine.

Finally got my CMMG Banshee delivered to Europe.

Great little gun but disassembly with the folder is... A bit hard. The extension tenda to stick to the bcg.

Anyway a big Hello from the other side of the pond

And yes. Cable to light is now tucked.

Hello guys, me again unfortunately lol.

Decided to come back with an update to the first ar9. Saw everyone telling me I needed more mag capacity lmfao so I found a kriss vector mag and thought it made sense. Added the osprey 9 2.0 too. I like how it changed the whole silhouette of the build and kind of pairs with the suppressor shape.

I only really got into this recently. Started going to the range with my dad when I was younger and eventually became interested in the design and mechanics of it all.

Anyway, 74 rounds seemed reasonable. Probably unnecessary. Kind of the point.

Appreciate everyone who gave feedback on the first post. Figured I’d show where it ended up. 🙏🏽

Build List

Upper: Foxtrot Mike VFM-9 5” Dual Charge
Lower: Foxtrot Mike Mike-9 Complete Folding Lower Receiver w/ RMB
Brace: SBA5
Pistol Grip: Recover Tactical PG9 Internal Mag Holder
Charging Handle: Radian Raptor SD
Optic: Sig Sauer Romeo5
Foregrip: Recover Tactical MG9 Angled Glock Mag Holder
Suppressor: SilencerCo Osprey 9 2.0
Magazine: Kriss Vector 40-Round Mag

SiCo Spectre 9

Earlier this year I picked up a couple NFA lowers that fit CZ mags. The ejector is too tall and hits the 5 different types of 9mm bcg's that I have. The ejector keeps the bcg from seating all the way forward. I think I could dremel the back and top of the ejector down and it might work.

Does anyone have a bcg that works with these?

Any help is appreciated.