Clip

Ammo clips are an ammo pick-up containing 10 bullets for the pistol or chaingun (20 at the I'm Too Young To Die and Nightmare! skill levels). The clips dropped by slain zombie troopers and SS Nazis contain only 5 bullets (10 at the I'm Too Young To Die and Nightmare! skill levels) and, unlike preexisting clips, disappear when crushed beneath doors or moving ceilings.

Each bullet does between 5 and 15 hit points of damage (determined using Doom's pseudorandom number generator). Note that this differs from the bullets fired by troopers and chaingunners, which inflict 3-15 points each.

Although referred to in the game as clips, the objects depicted are clearly magazines; that is to say, they contain bullets rather than merely hold them in place. 

Appearance statistics
The IWADs contain the following numbers of ammo clips (excluding those of dead Troopers):