Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to field strip a m 16 service rifle [title] Lock the bolt to the rear. [step] You will need to depress the lever on the charging handle and pull the charging handle all the way rearward. While holding the charging handle all the way in the rearward position you will need to push the bottom portion of the bolt catch located on the left side of the magazine well.

Ending1: This will lock the bolt from the backside of the magazine where it meets the chamber, where it may be opened differently. [title] Slide the firing handle, located at the rear, out of the chamber. Ending2: [title] Push the rear dis-assembly pin, located above the pistol grip. [step] This will allow the rifle to pivot on the forward dis-assembly pin for a " shot-gun " effect. Ending3: The bolt will not spring back on you until you release it. [substeps] The bolt catch on a rifle goes on the front of the magazine well while it is locked to the bolt foot. Ending4: The bolt catch is a looped piece of spaghetti tape. Once this hitch is in place set aside.

Answer format: ending1/ending2/ending3/ending4