AR-15 Buildathon is done...for now...

[JayBell]

I picked up my 2 AR recievers today...just finished the buildathon:
All dpms lowers
rear is freefloated heavy barrel, threaded for can, front/rear backup sights, scoped, with bipod...see other thread for particulars.

Middle AR is A2 upper/lower, bushmaster camo furniture, my 1971 Colt m16A1 barrel from my m16, 1/12 twist skinny barrel. this is the beater AR15, and has night sights on it.
This is due to the fact that the upper i bought used had a tritium flip aperature installed, so i boight a tritium front sight to match.

Bottom is the minty Colt m16A1 parts kit (semi internals of course) I got from Dan at Volunteer Ordinance Works for trade in FN/FAL parts, its all classic style M16a1 with triangle handguards, A1 grip, shorter buttstock, skinny barrel with birdcage FH and bayolug, and old 20rd mag
I even found a 60s/70s sling for it.




I think i'll get out the other ARs for a family portrait!

[phillyd2]

Looks good. I just got two LMT stripped lowers that I will need to install the LPK. Never done it before so I'm a bit nervous. Will wait for a snowy weekend to give it a try. I also have two DPMS lowers from Donnelly with the LPK already installed.

Now I have to decide what to do with these four lowers. I'm thinking one SBR, maybe 14.5" or 11.5". One will be a 16" for the Mrs. One may be a 9 mm - not sure about that though. Last one may be a 20" older style A1 - just thinking here but I really like the old school look of your Colt.

[aubie515]

I like the one with the vortex and flip up BUIS.

[JayBell]

I like the one with the vortex and flip up BUIS.

thats cuz you like the impractical-tactical type stuff, like me!

[DrakinClaw]

good stuff man. i like.
Drak

[JayBell]

the trouble fee guide to building your lower in 30 mins or less

no need to be nervous at all...its all horribly easy...of course, i've done it quite a few times.

some bits are 'tricky", if only that the procedure is awkward, you feel like you need the gunsmithing tool from Brownells, # 3RH000064583 "Hand, Third, one each"

some tips:
spread out a white sheet to work on, have a magnet around for spring and detent searching:-)

take your time, theres no rush, work in an oderly and logical fashion, noting how the assemblies work, and sometimes interlock to hold each other together

I do it in this order after CLP lubing all holes for FCG and takedown pins, follow this assembly plan.

front takedown pin:
insert the spring, then hold the detent pin point towards pin groove with thin needlenose pliers, insert pin, then use the pin to fully push it in and into the groove. (careful, spring can send detent flying!)

bolt holdopen:
Just fold up a tissue to a 2" square, and duct tape it to the side of the gun when installing the bolt holdopen rollpin.
get a long punch, use the method above to protect your lower. Carefully set the pin in the hole, give it a few taps, but not so far that it protrudes into the gap for the hold open.
now install the spring and plunger, and put the holdopen into the gap
Carefully drive the pin in making sure its lined up.
beter to tapa bunch of little times than big whacks.
be extra careful when the pin gets close to the holdopen protrusion, easy to slip with the punch and scratch it up.

trigger guard:
BE CAREFUL here, its easy to literally break off the tabs on the rear of the receiver.
install the front of the triggerguard by depressing the pin and snapping it in place.
slide the rear of the trigger guard in.
SUPPORT the triggerguard bottom tab on something firm, and non scratching.
carefully insert the roll pin, light taps.
Line up the rear of the triggerguards hole with the roll pin.
carefully tap the roll pin thru until its flush with one side.

magazine catch:
use a soft/plastic nonscratching tool to depress the spring and button all the way in to the tight side of the lower.
Insert the mag catch into the left side, and spin carefully. it should be perfect when the mag catch threaded portion is flush with the button on the right side.

fire control group:
trigger first, install the disconnector spring flared end DOWN in the hole provided in the trigger, its self capturing.
Trigger spring legs point forward, the front of the spring must be under the front of the trigger
Install the trigger pin, while lining up the disconnector, its a PITA, but not too hard, just wiggle up down back forth til the pin slides in.
hammer, install the spring so the legs are pointing down, and the loop goes behind the hammer.
the spring legs get depressed to the rear, and slot in on top of the trigger pin to hold it in place.
DO NOT DROP THE HAMMER ON THE HOLDOPEN...its not a Good Thing

then safety LAST...insert the safety, and flip the gun over and drop the safety detent in

install the pistolgrip, put the screw and star washer in the hole first.
slide the grip doen over the receiver tab, make sure you out the spring for the detent in the hole on the right side.
Tighten down the pistolgrip, do not kink the spring.
test the safety, it should have crisp clicks for safe and semi, and not bind.

rear takedown pin:
put the pin in the hole, slot facing the rear.
install the detent, point end towards slot.
dont kink or bend the spring...the buttstock will hold it in..as below


fixed Buttstock/tube/detent:
get the buttstock tube, and the detent and spring.
install the detent and spring in the hole by the rear receiver ring, press down while threading teh tube in, this will make a big dent in your finger.
thread the tube in, until it stops, the detent should only have the small pin sticking up.
use a wrench to tighten the tube.
if a fixed stock, install the spacer on the tupe, and slide the buttstockdown the tube, taking care not to kink or bend the detent spring above, for the rear takedown pin.
Slide fully forward, and tighten the screw.
cock hammer, and install the spring and buffer til the pin lock it in.
DONE!

collapsing buttstock:
pull the stock takedown latch OUT and remove the stock from the tube
orient the receiver lock plate so the indent will go on the hole under the receiver ring, and place the lock nut on teh INSIDE of the plate on the threads.
run the ring and plate all the way to the rear.
as above, install the detent and spring, and dent your finger.
carefully screw in the tube until the tab on the tube is indesxed to hold the detent in.
Install the rear takedown pin spring, and carefully work the lock plate down until it compresses the spring, and the indent locks into the hole in the receiver.
run the lock ring all the way down, and carefully tighten it, watching that the tube remains straight.
Wrench it down with the spanner wrench.
Install the sliding buttstock portion
DONE.

I think i have a blowup of a AR that shows how the springs orient if you need it.

its simple, and fun, and a neat design.