Welcome to the club.Just picked up a new Glock 42. Test fire date 5/2015. New "02" mags, etc. Fired 200rds today of fmj. Slide failed to lock open on last round 6 times today (6 mags out of 33 mags fired).
Is this a known issue or was it possibly just me with my thumb interfering with the slide release/catch?
Also, ejection seemed terrible. Ejecting right, up, back, almost no ejections to the right. Normal??
Other than that there were no malfunctions, every round chambered, fired, and ejected.
I'm on my 3rd G42 (no kidding, Glock replaced my original, twice). I've shot over 1100 rounds thru this 3rd one and it lock back on about every other mag or so. Mid mag mostly. Not just on me, a Range Officer and 3 others that have tried it. Don't believe the thumb hitting the mag release theory, it's a problem that Glock has not figured out, obviously.
I think think part of the problem is the Round Nose stuff as you will see others speaking of if you look thru other G42 threads. The XTP type of bullet does well, especially the "+P" ammo from Underwood.
Recently I've called Glock and explained it to the usual Tech guys and sense it is my 3rd one they "send me to a supervisor" who does not return my calls.
If I were you, I would call Glock and complain. They will send you a FedEx label for return and MAYBE fix it. I've read where others have had such good fortune, but not me. Best wishes and good luck! Herm