There probably are others. Some M1919 machine guns - originally in 7.62x63 (US .30-06) were later converted to utilise the 7.62x51 cartridge and M13 links. Other countries also made such conversions, although some retained the M1 links used for the .30-06 cartridge.
Machine guns are useful for killing people. They are also useful for aiming bigger weapons; since machine guns fire tracer ammo, a machine gunner can fire on a target so the forward observer can train guns onto it.
Depends on what type of machine gun. For most Western/NATO machine guns, the belts come packaged in 100 rounds on M13 disintegrating steel links, and these can be linked together to form as long a belt as one wishes. The linked ammunition for the FN Minimi/M249 SAW typically comes in 100 or 200 round linked increments. For your heavy 12.7mm/.50 machine guns, it's usually 100 rounds linked per box of ammo.
No, swords are weapons that don't run out of ammo like guns. Guns run out of ammo, not swords. Swords have infinite ammo. Their infinite ammo is their blade, not bullets. Guns run out of ammo and have to be reloaded. Some how, swords are better than guns because swords can deflect bullets. Guns uses bullets and swords uses blades.
Tracer ammunition are bullets that have a magnesium spot on the tail end of the bullet. This burns, usually red, and allows you to see exactly where the bullet is going. It's usually employed with belt-fed machine guns and is very effective at night. Typically, every fifth round in belted ammo is a tracer.
Unless there's a mod where guns use the same ammo, none
Fire discipline and ammo conversation, fields of fire, major avenues of approach.
No guns or ammo
The most popular magazine featuring guns and ammunition is "Guns and Ammo." Other popular gun and ammunition magazines include "Handguns" and "Shotgun News."
No. Machine guns will beat Gatling guns.
Machine guns.
yes
yes