Polymer80 AR-15 Member BUILD

Contributed by Gnashty Nordic

First Poly 80 AR Build


Set up is a harbor freight 10" drill press and 6" X/Y vise


Time to drill out my trigger control and hammer pins as well as the hole for fire select




So far so good



Here we hit a problem that I will show later. When I drilled the two holes straight through for the trigger, it happened to fall on the edge of a weaker section where I'm assuming they did the mold injection process. This led to a thin spot that was shallow from the outside. This was not due to over milling, but I fixed it with some good ol fashioned Jarhead improvising and JB weld. I mixed some polymer dust and JB weld to fill the defect and then milled back to spec.


Milling out the trigger pocket that will lead to discovery of said defect




So yea, everything was going great. Then my last pass with the mill, I went to raise the mill bit and it started to cut into right side chewing on the jig. I acted quick, lowered the mill bit and shut off press to remove the lower and inspect for damage. Luckily it was only a minor blemish. It will not affect functionality, but it sure did piss me off! Now I have to order another lower and start again! Lol. I will continue to finish this build until a new lower arrives!


Stock AR-15/M4 set up. Nothing fancy. Lower had tan paint from a test color I wanted to check out. Didn't like it. Wiped it all down to start a new.



Quick dry fit so I could see what I go


Now the real fun. Time to build this bitch



Fire control group installed. I may end up tapping a mark and back fill it for fire/safe. In case the wife needs to use. Also can't see as well but mag release installed. I must not have taken a photo of the bolt catch being put in.... Oops. But it's done too



Ejection port cover installed. The barrel has been greased and installed. The gas block and gas tube also installed. The forward assist was a bitch without a mag block for my vise. Should pick one of those up for future.

Installed take down pins on lower and installed stock tube and buffer assembly.

Installed standard carbine quad picatinny hand guard. A4 flash suppressor. Only need A4 front sight post and I have my best friend from Ar Ramadi back! (Nah looks cleaner without it)

Fully assembled and completed all functions tests! This baby is ready for some eyes and to hit the range! .... Once this Covid-19 restrictions end... 😞


4x prisim sight from monstrum. Red/green Dot. Not quite on par with my trijicon acog... But I'm not rich. So this will suffice until a better option is available. Got a great deal on the optic. Also started adding my Larue handguard inserts, but stopped because now I want to run a 45 ° offset sight in case main optic goes down or I want to shoot short range quicker. Will update once I find a sight I like.


So that's my build. First polymer 80 AR build. I have 2 poly80 G19 kits coming as well. I'm looking forward to getting my hands on them and getting back to the build. Never built a handgun before, so it will be a total new experience for me. My only weapon knowledge revolved around my AR, my 240 bravo, our .50, and my smaw rocket launcher. I'm always eager to learn a new weapon/weapon system. Hope y'all enjoyed the build. Looking forward to sharing my next 2.


Thank for checking it out! Keep on building!


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