Friend of mine just purchased a slightly used PT92 with a Lasermax sight and it doesn't want to slide lock on the last shot. It fires fine for the most part but it seems like the casing ejection is weak and then the slide wont lock on last shot.
Could this be because of the lasermax sight effecting the spring or is it more likely that the 9mm ammo maybe had a bad batch and isn't putting enough pressure out to make things work right?
Is it dirty? And how are you / is he gripping the gun? A weak grip on any auto will result in weak ejection and the slide not moving back far enough for the slide to catch on the lever.
Tell him to make sure he pushes forward with his shooting hand and pulls backward on the grip with his supporting hand. This will hold the gun firmly in place, allowing the slide to cycle without energy being wasted on rotating the gun backwards.
Excellent advice above. Also make sure he has/tries more than one magazine.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek
We both took turns shooting it, went through about...I dunno around 100 rounds. It functioned the same with both of us shooting it and using both magazines. We both grip properly and are experienced shooters, relatively experienced anyhow. I don't own a 9mm though and this was his first, we've both been .45 owners before. The 9mm version of the M&P I shot at the range didn't seem to shoot like this one, but it's a metal frame and the M&P is a polymer so I can't really use recoil as a comparison but it felt pretty light on the recoil and was easy to just fire off a whole mag as fast as I could and keep a 4" group.
Try cleaning the mags. If the follower isn't coming to the top of its stroke, or if it is slow in moving to the top of its stroke, it won't activate the slide catch in time before the slide starts its trip back into battery.
Taurus guns are packed with grease for shipping, and shooting one without cleaning it out really well will result in things really gumming up and causing problems that aren't the gun's fault.
My PT92 had almost 2k trouble-free rounds in it before I [regrettably] traded it for something smaller.
We just pulled it apart and checked it, the lasermax rod and the factory rod allow the spring to sit in the same location so we don't think it's that. We're gonna try some different ammo this weekend and see if that helps.