AR15 Wobble, Loose AR15
Receivers, Tighten.AR15
.This 18" Barrel Budget Build began with a stripped Anderson closed trigger lower receiver and a stripped Anderson upper, fit was surprisingly good so no shim was needed. The barrel is a Ballistic Advantage Wylde Chamber 1-8, stainless heavy. Flash hider and crush washer are Aero Precision,. The Gas Block is a steel Sadlak brand which is very close to a Diamond Head Block, the Sadlak has no extension and has three clamping screws instead of two found on the DH. Gas tube is a rifle length Melonite Aero Precision.
.
The M16 A1 length Buttstock Assembly from Fulton Armory has the A2 Trapdoor Buttplate, a 1/16" thick Cheek Eez pad was installed. A USGI Army Green Garand Sling was used on this build, sling silenced by inserting a copper box staple through the hinge and lining the hook with duct tape. A Talon brand 1 1/4" sling swivel came from an eBay seller. The charge handle is a Rise Armament RA-212. Some RA-212 handles can fit tight, cleaning the receiver channel and fitting may be needed. The BCG is an Angstadt Arms AA56BCGNIT from Bauer Precision.
.
The LPK is a ELG Enhanced Longitudinal Grind. The trigger and hammer were polished and along with dry fire, clean-lube and repeat to smooth it out. Nice thing about the LPK is the width on the hammer and trigger were spot on and did not require shims. Best thing about the worst thing was the hammer J-Spring was way too easy to remove however that made it easy for installing JP .156" oversize pins from Brownells.
.
A very sturdily and inexpensive Gun Broker 12.5" free float handguard item #898609929 was used. Some work was required for setup and time the beefy steel barrel nut with handguard alignment. The provided handguard attachment screws were too long and will dig into the barrel if not shortened. Six suitable size steel washers were shaped to fit the openings for the handguard attachment screws. Failure to include washers can cause the tightened Allen Heads to gradually sink into the aluminum and contact the barrel. Screws will have to be shortened some to avoid contact with the barrel. Verifying screw protrusion is easier with the barrel nut in the handguard prior to installation.
.
To align the handguard rail with the upper receiver the barrel nut has to be timed otherwise tightening the handguard attachment screws can pull the handguard off center. The barrel nut is timed when the top rail on the loose screw attached handguard twists side to side evenly in relation to the upper receiver rail. To help advance an already tight barrel nut a few degrees remove the barrel nut and clean all related threads with a brush, solvent and compressed air. Lube, reinstall, tighten-loosen and if necessary repeat the process. Note: Cleaning threads can cause some barrel nuts to travel beyond the desired point, allow room for that possibility.
The handguard used for this build has two threaded bores on the bottom front that make it easy to attach an inexpensive eBay seller Tilt Style 6-9" bipod. How to modify and attach the bipod direct to the handguard is in the Bipod section at the middle of the Budget Build page. To go rifle length gas and a bipod on a Budget the very nice GunBroker.com 898609929 handguard, the Optics Planet GB140S Sadlak Gas Block and the 6-9" Tilt Bipod are a good start.
.
An OpticsPlanet.com 2 dot Trijicon Rear Night Sight was installed on a detachable carry handle. Night sights are intended for USGI handles however some imports use the mil spec windage screw thread for a drop fit. USGI carry handle parts are available from JSESurplus.com.
.
Front Trijicon Night Sight Posts have mil spec threads and will fit some import gas block mounted detachable front sights or they have to be tapped.