The 8008 606

Exactly. Think about it. You are perhaps in enemy held territory. You may not have ready means of resupply. Your firearm may not use the same ammunition as the enemy's so you can't scavenge their supplies. Ammunition is like food. You don't waste it. Movies are ridiculous and feed into the fantasies that compel gun control advocates in the US.

You see people in movies firing 120 rounds from a semiautomatic pistol with a 12 round magazine without reloading, or "spraying fire" from a 30 round magazine for minutes at a time.

Now, the point of a heavy machine gun is to lay down a curtain of fire over a killing zone. That is not the point of small arms carried by individuals.

A significant point of fully automatic fire is for an emergency where one is suddenly facing several opponents. It is also used in the form of burst fire simply because the accuracy of most common issue military weapons except for specialized sniper rifles is not sufficent to butture a kill at range. Thus some weapons are equipped with a "burst fire" setting which discharges around three rounds with a single trigger pull, so the odds of hitting the target are vastly improved without wasting mbuttive amounts of ammunition, which, by the way, is quite heavy to carry.

Another issue is recoil. One reason for the movement to smaller caliber lower power weapons such as the M-16 and AK-47 was the difficulty for most people to control the muzzle rise of a weapon like a M-14 in full auto fire.

A second reason was a statistical analysis of infantry combat. It's much like what led to the development of RISC computing. It became understood that most infantry fire involved ranges of 250M or less, so it wasn't essential to have a weapon which could, given good sights and skills, kill at 1000M.

The ammunition for the less powerful weapons is much lighter, so soldiers could carry many more rounds and thus survive for longer duration missions without resupply.