Slide locking back while shooting-p10s

[ThePuebloKid]

Hi. As stated I have a p10s that the slide is locking back on while I am shooting it. I went to an advanced training class today (I'm on my churches security team) and during the drills that we were running my pistol began to malfunction. I was using some "generic" 115 gr FMJ "training ammo" that came from a large big box sporting goods store. The back of the box says "Made in the USA/Fabrique Aux E.U." and also has "2020 Federal Cartridge Company" AND "CCI/SPEER OPERATIONS" with Lewiston, ID. The casing is brass. Did I purchase some bad ammo or what? I have only had one other issue with this gun and that was with some aluminum case CCI Blazer rounds, and that was a failure to eject problem that was probably due to the gun getting hot. This is really weird. The instructor said he had never seen a slide lock back like this before. I would get off 2 or 3 rounds and it would lock back. I would have to pull back on the slide to get it to unlock and chamber the next round, would fire of 2 or 3 rounds and it would happen again. I was training using three mags and it happened with all three. I keep my firearms clean and oiled, so I don't think that was an issue. I'm hoping that there will be a simple solution/explanation for this. I REALLY like this gun, it is by far the most accurate, easiest shooting pistol I own. Sure hope someone has a solution for this....thanks!

[Grendel]

Two things to check:

1. Make sure your thumb is not hitting the slide catch under recoil - shoot the gun left handed to check

2. Take a look at the slide catch and see if there are any signs (brass marks) on it, signifying that the rounds are hitting it. You can also take off the slide and insert a loaded mag to see if there is any contact. It may well be that the ammunition you are using is loaded a fraction long for the 10. CZs are known for being sensitive to OAL and/or Ogive shape.

[ThePuebloKid]

Thank you for answering. I found a spot on the ejection port that has a brass "line" mark on it......good diagnosis (hopefully). Could you please elaborate a little more on what I am looking for as far as inserting a loaded mag? With the mag inserted the top round is in contact with the little arm that sticks out over the top back of the mag well (the rear insert?). I will also do an observation on how I am griping my gun/thumb location when I am shooting next. Also going to use some ammo that I know has worked flawlessly in the past. Gotta get this figured out....as I stated before I really, REALLY, like my gun. About 3 weeks ago I shot in two the 2x4 that was supporting my target--twice!

[Grendel]

Take a look at this thread about a similar problem with a 10S. There are some pictures included.

[ThePuebloKid]

Thank you all again for your attention and interest!! I think I found my problem last night while I was examining my gun with the slide off, mag inserted (thank you Grendel!). I noticed that the slide lock was very loose, would "flop" back and forth when I turned the frame over. I then noticed that the slide stop spring had come off the little, what, "shoulder" that it is suppose to be on. Took a couple of small flat screw drivers and slide it back on. Of course now the slide is not loose and stays in down position....gotta be the problem!! I'm going to go to the range ASAP and put some rounds through it (Noah's gotta land his boat first...raining like crazy today). I must of knocked the spring end loose when I was cleaning, I guess. Ill post a quick update when possible.

[ThePuebloKid]

Attention Grendel;
I made it out to the range this afternoon--Flawless Perfection!! Again, thank you for your help-I don't know how long I would of been struggling with this if it hadn't been for your advise. One more potential solution for down the road....

[Grendel]

Glad you got it fixed. Enjoy.