NOTE: DO NOT PULL THE CHARGING HANDLE BACK AND LET IT GO WITH THE DOLOS BARREL ASSEMBLY REMOVED. THIS WILL CAUSE THE BUFFER TO IMPACT THE BUFFER RETAINING PIN AND BREAK IT!!!!!
Information on the breakdown pistol set up:
Watch the video below for information on “Suppressor Safety”
9mm is the best set up in our experience. It’s a blowback system. There’s no quality difference between the Colt mag and Glock mag. There are notable differences: Glock magazines cost more than the Colt mags, but the Glock mags are easier to find at the retail level. Typically the Colt mags will cycle all types of ammo (brass, aluminum, or steel case) Glock mags tend to only like brass ammo. Also, you can use suppressors with either 9mm set up and there’s no worry of un-burnt powder build up no matter how short your barrel is.
Another note for PISTOL CALIBER AR’s: Pistol caliber AR’s require a bit more hammer strike to the primer. Not all triggers will work in 9mm, .40, or .45acp. Typically Mil-Spec triggers deliver plenty of hammer strike. Many aftermarket “drop-in” triggers do not work on pistol calibers. CMC Triggers, Timney, and POF are great triggers, but for pistol calibers, they DO NOT have enough hammer strike. Hiperfire Triggers are one of the brands that DO work on pistol calibers. They are not drop-in style triggers, and have extra technology in them to deliver the hammer strike needed for pistol calibers.
On the 223/556 and 300blkout, it’s a pistol gas system. The downside to this variant is the gas tube being exposed when the Dolos kit is removed from the upper receiver. This isn’t a deal breaker for the build, you just have to be aware that when your weapon is in the “takedown” condition, you have to be aware of the exposed gas tube.
Something to keep in mind when building/shooting 7.5″ 223/556, is most people want to run a suppressor on it because it’s so loud. This is a very dangerous practice! 223/556 on any configuration, should NEVER BE SUPPRESSED ON A BARREL LESS THAN 10.5″!!!!!!!!! This is due to un-burnt powder building up in the suppressor and igniting. DON’T DO IT! We recommend putting a Spike’s Tactical Barking Spider https://americanresistancegear.com/product/spikes-barking-spider-2-556223/ on your 7.5″ 223/556 build to help with sound and muzzle blast.
The breakdown pistol can also be built in 300Blkout. We recommend them in 8″ or 10.5″ barrel lengths. Reason for this is: 300blkout SHOULD NEVER BE SUPPRESSED ON A BARREL LENGTH SHORTER THAN 8″!!!!! Same un-burnt powder issue. However, for best results from our experience with sub-sonic ammo coupled with a suppressor, 10.5″ barrel length cycles more reliably. Our 10.5″ 300blkout uppers will come with a pistol gas system because the 300blkout doesn’t have the high pressure of the 223/556 and the pistol gas is needed for sub-sonic ammo. We’re not saying that 300blk will not cycle on 8″ barrels, it just takes a bit of tuning to get it right. This is based on many factors such as: gas port size, ammo being used, and/or gas block being used.
The 10.5″ 223/556 is a carbine gas system and much less pressure. Therefore, much less abuse on the internals.
Measurements 7.5″ set up: Put together ready to fire is 25 inches long. Folded for storage: 9.25″ long. Folded thickness: 5.5″. Height: 7.5″ from bottom of grip to top of upper receiver.
Measurements 10.5″ set up: Put together ready to fire is 28.5″ long. Folded for storage: 12.25″ long. Folded thickness: 5.5″. Height: 7.5″ from bottom of grip to top of upper receiver.