Ar15 Assembly ( Lower Receiver/ Magazine Catch)

Intro

At this point you should have completed the assembly of the upper receiver components, installed the barrel, the gas tube, the bolt carrier group, the charging handle, the front sight base and the flash hider. For this set of instructions we are using an aftermarket lower receiver parts kit. The lower receiver parts kit is a fast, easy way to get all the parts you need by ordering only one stock number. We will demonstrate the installation of the lower receiver components. Most aftermarket components install in the same way.

If you’re not using military configured parts, be sure you read and fully understand the instructions provided by the manufacturer. We will follow a specific order of assembly so that we don’t run into problems of parts interfering with each other. We will install the magazine catch first, then the bolt catch, the pivot pin, then the trigger group, followed by the safety selector and pistol grip and finally, install the trigger guard.

The tools that you will need are: the lower receiver vise block, a large tipped flathead screwdriver, bolt catch pin punch, number 3 and 4 roll pin holders and punches, a 4 oz. ballpeen hammer, your bench vise and a gun mat. You may find it helpful to have the pivot pin installation tool, it prevents the pivot pin spring and detent from launching out of your receiver while trying to install the pivot pin.

If you are installing a drop in trigger from Tactical Shit, they come with instructions and you can skip the trigger group install part.

Installing the Magazine Catch

You should only need the lower receiver vise block for assembling the magazine catch unless you’re

installing an aftermarket version, then you may need additional tools.

• 1. Tighten the lower receiver vise block into your vise and place lower receiver onto it through the magazine well. You can tilt the vise block and rotate your vise to better orient the receiver while you work on it.
• 2. Place the magazine catch into the receiver from the left hand side of the rifle.
• 3. Then insert the magazine catch spring followed by the magazine release button into the right-

  

  hand side.

• 4. Press the magazine button all the way in while controlling the magazine catch with your other hand. The magazine catch will be pushed back out of the receiver which will allow you to turn it.
• 5. Rotate the catch clockwise to thread it into the back of the magazine release button.
• 6. Use the back of a punch to push the magazine release button in until it is below the surface of the receiver. Continue rotating the magazine catch

  

  until the threaded shaft is even with, or just below, the surface of the button. Line up the magazine catch with the slot in the receiver and release the button.

• 7. Test the catch by pressing the release button, it should move without resistance and be prevented from rotating by the oblong hole on the right-hand side of the receiver. If the button rotates and catches, or the bottom of it is above the side of the receiver, you will need to turn down the magazine catch one more rotation to draw these parts closer together.