The Smith & Wesson "M&P 15/22" is a .22 caliber semi-automatic carbine that uses the same basic design as the Colt AR-15 rifle. The carbine comes standard with a 25-round magazine and is chambered specifically for the .22 LR rimfire round. Like all AR-based rifles, the M&P 15/22 is designed to break down simply and quickly for cleaning, maintenance or repair.
Remove the carbine's magazine and pull the bolt back. Inspect the firing chamber to ensure there is no live ammunition in the weapon, then close the bolt again.
Push the take-down pin located on the left side of the carbine all the way through the right side of the rifle and remove it completely. The pin can be found at the back of the carbine, just in front of the stock assembly.
Pull up on the upper receiver and pull down on the pistol grip gently. The rifle will come apart and the barrel and upper receiver will pivot downwards.
Pull the bolt assembly and charging handle straight backward out the back of the upper receiver.