How to Disassemble a M4 Ar15

Point the muzzle down range in a safe direction. Press the magazine catch on the left side of the rifle to drop any magazine still present in the rifle. Pull the charging handle located on the top of the rifle straight back to open the bolt and eject any remaining live rounds. Visually inspect the chamber to ensure no live ammunition is present in the rifle.

Tap the rear retaining pin out of the lower receiver from left to right with the hammer and large pin remover. A detente prevents the pin from coming completely out. The upper and lower receivers open like a clam shell. With the pin remover and hammer, tap the front retaining pin out. Another detente prevents it from coming out. Pull the upper and lower halves apart.

Hold the upper receiver upside down, and pull the charging handle to the rear. Lift the bolt assembly out of the receiver as it slides out the rear with the handle. Remove the charging handle when it reaches the notch at the rear of the receiver. At this point, the rifle is considered field stripped for basic cleaning. Additional disassembly is only required for repair or rebuilding the rifle.

Press the buffer tube assembly into the stock. Press the retaining tab down, and slide the buffer tube and spring from the stock.

Mount the lower receiver assembly onto the AR-15 lower receiver block and place into the vice. Carefully loosen the castle nut with the castle nut wrench. A small retention plate slides to the rear. Remove the small detente spring and detente from the rear of the lower receiver. Remove the rear retention pin.

Rotate the entire stock counter clockwise to unscrew it from the lower receiver. Keep an eye on the buffer tube retention tab and spring. Capture and remove it when the stock is removed enough to allow it to come out.

Turn the rifle upside down. Remove the long screw holding the pistol grip to the rifle with a screwdriver. Avoid losing the small spring and detente on the bottom of the receiver as you remove the grip. Removing this spring and detente allows the uninstallation of the safety.

Remove the lower parts kit. With the pin remover and hammer, gently tap out the two pins holding the hammer and trigger assemblies in the lower receiver. Set the lower receiver and parts aside.

Pull the forearm retention ring toward the rear of the upper receiver until the two halves of the forearm guards loosen. Separate the halves of the guards, and remove them.

Tap the roll pin holding the gas tube in the front sight assembly with a small pin remover and hammer. Slide the gas tube out of the rifle through the upper receiver until it clears the front sight. Slide the tube forward and out of the rifle.

Mount the upper receiver in the upper receiver block, and place into the vice. Push the armorers wrench onto the barrel nut. The nut is under spring tension; press the nut toward the receiver as it is turned counter clockwise until the barrel comes free. With the snap ring pliers, remove the snap ring, spring and delta ring from the barrel nut.

With the small pin remover and hammer, remove the roll pin retaining the forward assist. Slide the foward assist and spring from the receiver.