Dangerous flaw in Army's M4A1 rifles

A soldier fires an M4A1 during training. Army Times. 

A dangerous flaw in the US Army's M4A1 rifles can cause the rifle to fire without pressing the trigger. Army Times. The malfunction occurs when the rifle's selector switch is set between semi and auto. The rifle will not fire but it will fire off a round when the selector switch is put back into semi or auto. The Army thinks that the flaw could extend beyond M4A1's and the original M4's and M16A4's as well. The rifles in question are part of the rifle improvement program that converted M4's to M4A1's, which gives the rifle a heavy barrel, ambidextrous safeties and full auto fire capability as opposed to burst fire. The Army released a new function check for all M4A1's, M4's and M16's.

1. Ensure weapon is clear by observing the chamber, the bolt face, and magazine well. The weapon should always be pointed in a safe direction.

2. Charge the weapon, place selector lever on the safe position and pull trigger. The hammer should not drop.

3. Move the selector lever to the semi position, then move the selector to a position between semi and auto, and squeeze the trigger. The hammer should drop when the trigger is squeezed. If the hammer does not drop when the trigger is squeezed, this is a failure. Record this information and continue to the next step.

4. If the hammer does not drop, move the selector in either direction. If the hammer drops without squeezing the trigger, this is a failure. Record this information.

5. Gather information recorded from failures at steps (3) and (4) and segregate the weapon for further investigation. Contact TACOM with the weapon serial number.

6. If the weapon passes steps (3) and (4), the function check is complete.

My Comment:
I've had some experience with guns and I can't think of a worse failure than a gun firing without pulling the trigger, short of an explosive failure. Though if you are following basic gun safety rules this malfunction should not be an especially dangerous one. Guns should be pointed down range at all times and you should never point a gun at something you aren't willing to destroy. In theory that should prevent any kind of unintentional shooting.

In combat though, this flaw could be extremely dangerous. Not having a round fire off when you expect could be the difference between life and death during a battle. And having it go off during conflict is much more dangerous than during a range situation. Either way it could have caused someone to die.

Thankfully, this malfunction seems fairly rare to have happen. Having the selector switch between full auto and semi auto isn't something that would happen that often. And it doesn't seem to effect all rifles. Still, having your gun go off without pulling the trigger is not something that you ever want to happen and it is good that the military caught this flaw now.

It seems like this flaw only effects M4's that have been upgraded to M4A1's. Those rifles were upgraded after battle experience in Afghanistan, but the flaw is because they decided to switch the rifle from burst fire to full auto. Why they did so is unknown to me but it seems like it has caused this issue. Hopefully the effected rifles will be fixed soon.

Of course, this malfunction will not effect civilian owned AR-15's as none of them have selector switches that can go between full and semi auto. All civilian AR's have is safe and semi, so owners of AR's have nothing to worry about.