Last weekend I had an extended range session during my time there I put about 400 rounds of mixed ammo down range through the m+p15. Eley sport cci ar tactical and mini mag. About 16 magazines in all I think my bolt hold open worked 3-4 times and if I remember right that was with the slower velocity eley sport. I have 3 magazines and all mags are affected. I have maybe 1500-2000 rounds through this gun and I would say that the bolt hold open has worked 90 percent of the time before the weekend. Any ideas of a fix anyone ? As I don't want to count rounds or hear that click of my firing pin going on an empty chamber

Try reading this old thread on this issue, it may shed some light into your problem.

Last shot hold open

My new sport had a simular problem with the 25 round mags

but not with any of my 10 round......

I had noticed a lot of sideways movement on the bolt hold open

"button"

My cure was to use two 2.5mm stainless steel washers,

these where adjusted to slip either side of the "button"

This seems to of cured my problem







keith

Thanks. After reading the old posts I have taken a coil of my spring. I will try that first. Will let you know if it's fixed after the next range trip