Here's my CMMG Radial Delayed Blowback 9MM Frankenbuild.

[ysr_racer]

Here's my CMMG Radial Delayed Blowback 9MM Frankenbuild. It's a 9mm PCC with no gas system.

It's some spare parts, some new parts, and a CMMG Radial Delayed Blowback 9MM barrel and bolt.

It's SOFT shooting.

I'm still working on it. The Glock mags still sit too high. I know I have to file down the mag catch, but in the mean time, I just opened up the notch on the mag. I also removed the ejector since the RDB bolt has one like an AR15.

Here's my parts list

CMMG Radial Delayed Blowback 9MM barrel and bolt
Aero XL upper
Aero EPC lower
Juggernaut Tactical Cal-stupid grip
Gunshow handguard
Rifle buffer tube
Carbine spring and buffer
ALG Advanced Combat Trigger (ACT)
Lead Star stock
EBay $20 muzzle break

The bolt still drags over the mag, and my brass is scratched. It's a work in progress.

[2017mini14]

[ysr_racer]

What is the weight of your buffer? ALG triggers work fine in AR9’s?

I'm running a stock 3oz carbine buffer and a stock carbine spring in a rifle length buffer tube. There's VERY LITTLE spring pressure holding the bolt carrier in place.

The RDB Radial Delayed Blowback bolt carrier is the same size as an ar15 bolt carrier, so any trigger works. Most PCCs use a proprietary bolt carrier so they sometimes need a taller hammer to reset.

That being said, my ALG trigger blows. It's at 5 pounds which is fine, but it's got a TON of creep and mush in it.

[2017mini14]

Only a 3oz buffer? Is there extra weights in the BCG? That is an Interesting rifle.

[bohoki]

Only a 3oz buffer? Is there extra weights in the BCG? That is an Interesting rifle.

it shouldn't need mass in the buffer since the radial delay uses mechanical disadvantage to push the carrier back also since it has a bolt and carrier you want an actual buffer to counteract any carrier bounce

i got only 2 questions

#1 how does the rear take down pin stay in place without a "plate"

and #2 what is up with the aluminum foil?

[ysr_racer]

Only a 3oz buffer? Is there extra weights in the BCG? That is an Interesting rifle.

3oz, I'm going to open it up and gut it. It only needs to weigh 1oz. The bolt stays locked into the barrel for a few extra mila seconds.

This isn't direct blowback.

[ysr_racer]

it shouldn't need mass in the buffer since the radial delay uses mechanical disadvantage to push the carrier back also since it has a bolt and carrier you want an actual buffer to counteract any carrier bounce

i got only 2 questions

#1 how does the rear take down pin stay in place without a "plate"

and #2 what is up with the aluminum foil?

1. The Aero EPC lower has a threaded hole and set screw to hold the spring in place. No plate needed.

2. Gucci

[ysr_racer]

It's a Frankenbuild, and I ran out of duct tape

[ysr_racer]

I'm not sure if the buffer ever makes it to the back of the rifle length buffer tube, it's that soft.

[drclark]

Cool.. if sbr ever becomes attainable in CA, I would be all over something like this.

The concept of the delayed blowback is cool and essentially inverts the operation of the "locking lugs" and bcg cam action for pistol caliber

[bohoki]

wait it just hit me that is a rifle tube so isn't there the typical rifle buffer in there and it would be 5oz i think

[ysr_racer]

wait it just hit me that is a rifle tube so isn't there the typical rifle buffer in there and it would be 5oz i think

Yes, in a direct blowback gun, but mine is radial delayed blowback. If I run a carbine buffer tube, I need to run a 1oz buffer.

Yeah, it's that soft shooting

[Nvberinger]

It's a Frankenbuild, and I ran out of duct tape

Man that looks hideous.

[CheapBloke]

It's a Frankenbuild, and I ran out of duct tape

Looks more like r/PlebeianAR.

Sent from my SM-N960U using Tapatalk

[ysr_racer]

Man that looks hideous.

Don't hate me because I'm beautiful.