In our weapons shop, we’ve noticed some Soldiers have cleaned their M249 gas piston assembly and left cleaning patches or other cleaning material behind inside the weapon. If the gas system is blocked, it will prevent the gas piston assembly from completing its cycle, which can cause a malfunction.
After Soldiers clean their M249 gas piston assembly, we suggest they shine a flashlight in the gas hole and make sure there is no obstruction.
Gas port hole
Also, they can look down the hollow tube of the gas piston assembly to make sure there are no obstructions.
Shine a light into the gas port hole
Fred Fanning II
Ft Leonard Wood, MO
Editor’s note: Thanks for the pointers, Fred, Mark and David. Operators, heed the advice and keep your M249 firing smoothly.