NEWS | Nov. 18, 2019

M16-Series Rifles, M4/M4A1 Carbine: Solving Loose Lever Mystery

Dear Editor,

We’ve had a problem at Ft Leonard Wood with the M16 and M4’s right-side fire control selector lever working loose and sometimes disappearing.  

We suspect the reason is from armorers forcing the weapons to fit into M12 racks. Over time, that loosens the lever’s screw.  

As PS has pointed out in the Oct '19 issue, older M12 racks must be modified so that M4s and M16s with the new fire control selector lever will fit. If a weapon won’t slide easily into the rack slot, then the rack probably needs to be modified. Armorers should tell their small arms repairman. But never force a weapon into a rack.

Soldiers need to check for a loose right-side selector lever when they do PMCS. Repairmen can tighten the screw with a 7/64 hex wrench. Coating the screw with sealing compound can help it stay tight.  

 Robert Castanieto
 Victor Jackson
 Richard Hallas
 Ft Leonard Wood, MO
Editor’s note:  That’s another good tip from the FMX weapons repair shop. Check out the story on Pages 42-43 of PS 803 (Oct 19):
It shows you how to modify racks with welding pliers or a mini-sledge hammer.