M4/M4A1 Unintentional Discharges Fix

[Alamo]

https://taskandpurpose.com/army-fix-glitch-m4-carbines/

Tolerance stacking issue.

After more than 50,000 weapons were checked, TACOM officials discovered the cause of the glitch and halted the inspections, TACOM spokesman R. Slade Walters told Military.com.
“After receiving a significant number of reports from the field and an average failure rate of about 6 percent of the weapons inspected, we ended the inspections and have determined that the cause of the problem is a tolerance stack of the internal firing components,” he said in an email. “The problem is fixed by modifying the selector to remove the tolerance issue and the fault. TACOM is working on an Army-wide directive to repair weapons with the issue that will be released when it is approved at the appropriate levels.”

The glitch-testing started when a Fort Knox soldier’s M4A1 selector switch became stuck in-between the semi and auto settings. When the soldier pulled the trigger, the weapon failed to fire. The soldier then moved the selector switch and the weapon fired, the TACOM message states.

By far most common among M4s converted to M4A1.

 

[Disposable Heart]

I guess the older M4s were "worn in" or had egged out FCG pin holes, causing some issues with clearances with the new full auto FCGs they were trying to shove in...

Makes me wonder: Juice vs. squeeze. What would have cost more?
A. Having armorers or subcontractors retrofit existing M4 carbines (so you're out parts cost for retrofit, armorer time or worse, contractor time, testing then arsenal)
B. Buying M4A1 carbines new, selling/donating older M4 carbines to SE Asia, Africa as hedge against China? Heck, the Middle East are suckers for our old stuff, Israel particularly, they like buying up second tier stuff that we cast off...