That's what the Secretary of Defense McNamara ordered during the Vietnam War; until another Secretary orders it different, that order will stand.
Yes, along with the carbine version of the M16, the M4.
the m14 came into use just before the Vietnam war but scince it was heavy and the recoil was bad in full automatic it quickly was replaced by the M16 but still used it as a sniper rifle and marines today are dusting off old m14s and using them as sniper rifles
Not entirely. The Marines retained the M16, and most Army mech units opted for the M16A4 rather than the M4.
I think you mean "Rifle"- the M16. Guns are machineguns, cannon, or shotguns.
Like any professional sane soldier from any where around the world, the US Marines prefer the semi-automatic rate of fire.
The M14 rifle is indeed still in use by the US military. While most soldiers are issued the M16 , or the carbine version of the M16, the M14 is still used where longer range fire and greater penetration may be needed.
the m16 uses 5.56 caliber ammo
A lot of soldiers use AR15s these days. Some still use the M16. This is a very generalized answer,but I hope it is useful.
You should use a m16 because its better.
m16
During a time which the US military was fielding a .30 weapon (M14 rifle), jungle warfare required a weapon that was lighter and could "put the lead out." The M16 could do this. Consequently, the M16 was sent to Vietnam as a jungle rifle; all other US forces (army, marines, navy, air force was the only exception) retained their M14 rifles around the world. ONLY troops in Vietnam received the jungle rifle (M16). Until after 1970...then the M16 began to replace the M14s.
5.62mm I believe.