How to Combine the AR-15 Upper and Lower Receiver

When the upper and lower receivers of an AR-15 are ready to be joined together, the steps are relatively simple. The pivot pin secures these two receivers. With the hammer cocked and the safety on, place the two receivers together aligning the front pivot pin bosses.

Now push in the pivot pin.

To tighten the fit between the upper and lower receivers, I'm installing an accurizing wedge.

Simply place it in the lower receiver under the takedown pin with the high side to the rear.

Insert the charging handle and bolt assembly.

Now pivot the upper assembly back and hold it down with some pressure on the carry handle.

That's all there is to it.

--Larry Potterfield