A pin like object is located directly in front of the butt stock which prevents the spring exiting. Push down on this pin and the spring shall depart easily. This spring can be released from the butt stock. Upper Receiver and Barrel Assembly M16A2 9349050, and M4 and M4A1 12972680. This copy is a reprint which includes current pages from Changes 1 and 2. The Parts. Lower receiver group assembly. I have put together a visual guide to help you easily understand the process involved in putting together your first rifle. This unit accurately locates (held within .001”) the 2 drilling holes as well as depicts not only the shape but also the depth specifics of the select-fire control pocket layout. Insert the buffer assembly into the recess in the stock of the weapon. The lower receiver parts kit consists of 30 parts not counting the stock assembly, the receiver, or the pistol grip. It is a good idea to lay all your parts out on a flat, light-colored surface so that you can verify all your parts are there, and find them easily when you need them. Lower Receiver Inside the butt stock of the lower receiver, there is s spring. To complete the lower you will be drilling three holes and machining two pockets. How to build an AR-15 Lower Receiver: A Step by Step Visual Guide. Buffer Tube Assembly The AR-15 Lower Receiver Parts Kit consists of the following: This is a step by step guide on how to build an AR-15 Lower Receiver in 8 easy steps from a stripped receiver and a lower receiver parts kit. Figure C-6. M-16 lower Parts kit includes everything that goes inside your M16 lower receiver. This complete 3D printer-made jig assembly is designed specifically for AR-15 mil. TM 9-1005-249-10 OPERATOR’S MANUAL FOR RIFLE, 5.56-MM, M16 (1005-00-856-6885) A full parts kit will include an M16 sear, sear spring, sear pin, a buffer detent, a buffer detent spring, an A-2 pistol grip, a pistol grip screw, a pistol grip screw washer, a bolt catch assembly, a front pivot pin, a mag catch assembly, a rear takedown pin, two takedown pin springs, two takedown pin detents, an M16 fire control group, and all pins and springs for the fire control group. ASSEMBLY OF THE Ml6/M4 CARBINE RIFLE. We only sell the best bolt carrier group, because we understand the crucial role it plays in the function of your AR-15. spec. Depress the buffer retainer so that the buffer assembly will insert into the recess completely. To keep the lower receiver within tolerance, pay close attention to the tolerances as you machine. AR-15 Lower Receiver Parts Kit 2. If you're looking for the best bolt carrier group for sale, you need to shop with Surplus Ammo. In order to avoid violations of the NFA, M16, hammers, triggers, disconnectors, selectors and bolt carriers must not be used in assembly of AR-15 type semiautomatic rifles, unless the M16 parts have been modified to AR-15 Model SP1 configuration. TM9-1005-319-23LP 3 4 5 DESCRIPTION AND USABLE ON CODE UOC GROUP 03 Press hammer to the rear (downward). These instructions are meant to give you some direction in completing your Optimus Defense 80% Lower Receiver. Building your first AR15 lower receiver can be a daunting task. receivers for use by Type 07 FFL's/Class 2 SOT's. Release the pin so the buffer assembly is locked into place. AR-15 Lower 3. Parts Needed: 1.