I understand the reasoning by putting full auto capability on a heavy machine machine/SAW to provide suppressive fire, but why would you want one on a M4 or others similiar weapon to that?  IMO, it is waste of ammunition and that you really can't hit anything.  I guess this is the reason why the Military went from full auto to 3-round burst after the Vietnam war.  

For all you wise guys out there, don't give me the answer that it is cool.

Any other comments/opinions to this logic?

Suppressive fire works.

CQB? Though maybe an mp-5 and not an m-16 would be better.

I'd rather have the option to go auto and not need it, than not have the option; and need it.

Quoted: I understand the reasoning by putting full auto capability on a heavy machine machine/SAW to provide suppressive fire, but why would you want one on a M4 or others similiar weapon to that?  IMO, it is waste of ammunition and that you really can't hit anything.  I guess this is the reason why the Military went from full auto to 3-round burst after the Vietnam war.   For all you wise guys out there, don't give me the answer that it is cool. Any other comments/opinions to this logic?

Are you talking regular Army...Special Forces...SHTF?  I think full auto is a requirement for a small force so as to be able to more easily break contact with an enemy force as needed or desired.  The squad won't always be in a position where the full auto guy can cover and be the last one to egress.  

Quoted: I understand the reasoning by putting full auto capability on a heavy machine machine/SAW to provide suppressive fire, but why would you want one on a M4 or others similiar weapon to that?  IMO, it is waste of ammunition and that you really can't hit anything.  I guess this is the reason why the Military went from full auto to 3-round burst after the Vietnam war.   For all you wise guys out there, don't give me the answer that it is cool. Any other comments/opinions to this logic?

With short controlled burts I can hit my target every time.

Would you want to clear a building or a room with a semi-auto? Full-auto does have it purposes but what you need to understand is the M-16 rifle was designed first and foremost to be a semi-auto rifle with full-auto capability while something like an AK is designed more in-line like a sub-machine gun with semi-auto capability. It really all boils down to training and who would be doing the fighting and you can see why each rifle was designed the way it was.

Quoted: I understand the reasoning by putting full auto capability on a heavy machine machine/SAW to provide suppressive fire, but why would you want one on a M4 or others similiar weapon to that?  IMO, it is waste of ammunition and that you really can't hit anything.  I guess this is the reason why the Military went from full auto to 3-round burst after the Vietnam war.   For all you wise guys out there, don't give me the answer that it is cool. Any other comments/opinions to this logic?

I guess you just had to be there...

Quoted: Suppressive fire works.

Yep. The enemy just needs to hear the shots and the bullets plinking their general area to keep them pinned down.

It is fast, often faster than most people can pull the trigger. It can really help to fire two or three rounds in the same sight picture, especially when you know what you are doing and can keep them tight.

Armed confrontations seem to be, for the most part, quick and violent. Most are over in a matter of seconds, with the really long ones typically not lasting for more than an hour.

During this time, everyone is moving, and everyones goal is to kill the enemy. People have kept fighting after taking a 5.56 round to the chest. Not many keep fighting after taking three.

The military went to three round burst after Vietnam largely because guys were using M-16s like bullet hoses, ripping off mag after mag and, frequently, not hitting anything. This led to troops on the ground with no ammo, and the logistical problems that follow. With a three round burst you have to pull the trigger 10 times to empty a magazine, and there is no illusion that you must have hit something with all of that fire.

It was a mistake to remove continuous fire from the M16/M4 platform.  For sure, lots of ammo was needlessly wasted during the Vietnam war, but one of the best uses of full auto is to "make ten feet of wall uninhabitable REAL fast".  In otherwords, it's highly useful in urban combat and guess what?  Now we're engaged in close quarters urban combat in Iraq.

IMHO, it's to provide flexibility. Yeah, you can have a SAW gunner to provide suppressive fire, but what if the battle didn't go as planned, and you need some suppressive fire somewhere else? With select-fire rifles, anybody can do it.

In a close-quarters environment, it also makes it faster to put 2 or 3 rounds in someone before moving on to the next target.

Suppressing fire
Superior firepower (its a psychological thing - keeps their heads down)

It's also sheer volume of fire to keep the enemy's head down. The SAW with its heavier weight, stable bipod provides higher sustained rates of fire. Also the ability to absorb more heat and larger ammo capacity.