Hello!

I am from Israel and, like most of our citizens, i have served several years in the IDF.

We usually use the semiautomatic mode for M16 or any gun from the family for tactic reasons, but there is a myth, that says, that if the gun fires automatically several clips, it gets overheated. Then the bullet, which is automatically loaded, fires because the heat detonates the gunpowder, the gun reloads itself and keeps shooting.

Thanks for your attention!

ANY automatic weapon can become a runaway gun if it overheats and begins to cook off the round in the chamber. Closed bolt systems (like the M16 and AK series) were not meant to be fired on full auto for extended periods of time. In semi-auto, unless the sear is damaged, a cook-off will result in only one shot being fired.

Overheating a Magazine fed gun is going to be very difficulty since you have to stop and swap put clips every 30 rounds. This gives the barrel a chance to cool slightly.

This is more of an issue with belt fed guns.

Thanks for the reply.

Actually, i know all that. I also know, that early AK does not usually overheat so much, and i personally saw an attempt to overheat Galil. But M16 fires faster, it can be reloaded faster and without a need to pull (how do you call it?) this handle, which becomes very hot in Galil. On the other hand, i am not sure that under any circumstances it can reach sufficient temperature inside...

That's why a lot of machine guns fire from the open bolt.
We saw an occasional "cook-off" with the M-14 and also the M2 .50 machine gun. Usually, since the trigger isn't depressed, you just get the one round.

Armynurseboi, question for you:

Why would it matter if the gun is in semi-auto mode? Wouldn't it still cook off the round and chamber another one which may also cook off? Is there some mechanism that prevents the bolt from cycling in semi-auto mode unless the trigger is pulled and reset?

[quote]Armynurseboi, question for you:

Why would it matter if the gun is in semi-auto mode? Wouldn't it still cook off the round and chamber another one which may also cook off? Is there some mechanism that prevents the bolt from cycling in semi-auto mode unless the trigger is pulled and reset?[/quote]

When a closed bolt select fire weapon is in semi-auto mode, the sear prevents the hammer from falling on the firing pin after it has cycled until the trigger is pulled again. So, if the sear is not damaged, it will cook off , cycle once and stop.

I have never had an M16 series rifle get so hot as to cook off a round, the magazine changes pretty much kept this from happening.

I have had M16s really, really hot (FPF scenario), but never had a cook off.

Never had a cook off in a belt fed, due to belt changes and barrel changes. (to prevent overheated barrels)

army: I understand that, but in this case, since it is the heat around the cartridge that causes the round to fire not the firing pin hitting the primer, why should it matter what the hammer does?

Basically, if there is enough heat to cook off one round it seems like a reasonable assumption that the existing heat plus the heat added by that round will also be enough to fire the next round. If nothing physically prevents the bolt from cycling why would the process stop, semi-auto or not?

[quote]We saw an occasional "cook-off" with the M-14 and also the M2 .50 machine gun.[/quote]

A cook off with the M14! Semit-auto with 20 rd magazines? What were you using? An M14E2/A1?

Not trying to challenge you here. I had limited hands-on work with the M14 (qualified in training on it, but had the M16 once I joined a unit), so I've no experience with the weapon getting that hot. Learn something new every day, I guess.

The M-16s have now been changed, as they no longer have full auto capability. Now you have single semiauto fire or three-shot burst.

I've fired an M-16 so hot I could feel the heat through the hand guards. I agree that the magazine changes keep it from getting too hot.

Stovietspyguy

Vnature. Of course it does not matter, whether the gun is in semi, auto or even safe mode. And the fact, the none of the forum visitors could overheat the gun so much does not change a thing too.