The M14 appears in the level "SOG," and is used by various US soldiers, mostly with an ACOG, a Grenade Launcher, or no attachments. It also has Dusty camouflage applied. Aside from being dropped by friendly soldiers, one can be found beside an M16 in one of the ammo bunkers before throwing the napalm barrels down into the NVA trenches.
The M14 is the third assault rifle and the first semi-automatic assault rifle unlocked, costing 2000 and it may be purchased at level 9. The M14 features a 20 round magazine (30 with Extended Mags), medium recoil, high damage, killing in 2-3 shots in core game modes and is best suited for medium to long range combat. As such the M14 benefits greatly from sights and scopes. The M14 is comparable to a sniper rifle when both the ACOG Scope and Grip are attached. The ACOG Scope for the M14 largely renders the M14's upward recoil inconsequential since the cross-hair is so thin, this combination will defeat most other guns at mid range (almost certainly at mid to long range) if the user aims well, and using Hardened Pro is very useful at longer ranges, as flinching with this weapon is often fatal. When used with the Grip the M14's recoil is as manageable as possible, as the gunsights resettle after each shot quite quickly.
The M14 technically performs poorly in close quarters because it is a semi-automatic weapon. This can be remedied by using the Flamethrower or Masterkey. A player with a good trigger finger does stand a chance against other weapons when hip-firing, due to its ability to kill with two shots. Steady Aim also helps quite a lot if the player is fine with hip firing the M14.
The M14 can fit a variety of roles, from a designated marksman to a medium-range stealth class. Sleight of Hand is not immediately necessary, as it has a fairly large, 20 round magazine and a fast reload, potentially allowing for 10 kills before the need to reload arises. A more useful perk for a class using this weapon would be Hardened or Warlord, as an M14 with a Grip and sight is an accurate, deadly weapon with low recoil.
The M14 can become extremely useful in Hardcore modes. In Hardcore, the M14 kills in one hit, so in combination with an ACOG sight and Suppressor attachments it can become an excellent light sniper rifle with low recoil, and large magazines.
The following attachments are available for this weapon:
Red Dot Sight
The M14 is the only assault rifle to accept a Grip, as well as being the only assault rifle next to the G11 not accepting the Dual Mag attachment. Unlike most Assault Rifles, the M14 when paired up with optics, the iron sights are not removed as it is impossible to do so.
The M14 appears in all 4 Nazi Zombies maps Kino der Toten, "Five", Ascension, and Call of the Dead. The M14 is a fairly decent weapon to start with since it can be purchased off the wall in all 4 of the maps for 500 points in the first room, though it rapidly loses its usefulness since it has an eight round magazine instead of 20. In Kino der Toten, if the player looks at the stairs from the spawn, they will find the M14 on the wall at the top of the stairs on the right side of the starting room. In Five, if the player looks towards the large television screen from the spawn, they will find the M14 in the back along the wall to their left. It is best used in the early rounds as in round 5 it takes almost an entire magazine (of body shots) to kill a single Zombie, but one can hold off for a few more rounds if going for headshots. Ammo can be bought off the wall for 200 points as well as upgraded ammo for 4500 points.
Upon using the Pack-a-Punch machine with the M14, it will become the "Mnesia", which increases damage along with having a higher rate of fire and a 16-round magazine with 192 extra rounds. This weapon seems to trigger quotes from all of the characters, usually dealing with its weight. In comparison, the M14 is almost equivalent to the M1 Garand and their iron sights are the same. The M14 also appears to have the same power per one bullet as knifing. This can be proven in the earlier rounds.