Walther P99 slide releases when mag inserted.

[Dand]

I bought a used P99  .40 S&W  and have fired about 50-60 rounds so far.
 
Today when I inserted a loaded magazine, the slide release let go and carried a round into battery without me touching the slide release.  I had pushed the magazine into position pretty vigorously.
 
It was a chilly day and I was wearing gloves, so I wondered if  I had accidentally hit the slide release.
 
I repeated the procedure several times bare handed and with great care to avoid touching the slide release or mag releases.  Sometimes the slide would drop and sometimes it didn't. When I inserted the magazine slowly and gently, the slide never released.  Rougher treatment was more variable. It never happened with just an empty magazine.
 
Am I being too rough?
 
Is the gun supposed to release the slide so easily?
 
I would much rather the slide remain locked open until I intentionally release it.  It could be too easy to have the gun pointed in an unsafe direction to have it drop automatically, leaving the weapon cocked and ready to fire.
 
I looked at the slide latch notch and the actual catch surface where the release locks the slide and I don't see any damage that is obvious to me. The notch in the slide is not real deep but seems adequate and has a square should for the catch to engage.
 
Any comments or suggestions?
 
I really like the fit, weight, feel, handling, and accuracy of this gun from my limited testing.  It might replace my Ruger SP101 if I feel its safe and I become more confident with it.

I've posted these questions to Walther America as well.
 
thank you
 
Dan

[4MUL8R]

Are you shooting FMJ?  Are you certain that the bullets are not hitting the slide release when they are rammed upward?  Sounds crazy, I know.  But, if the cartridges are not at the rear of the magazine and the bullets are bulbous I have seen a Glock G36 show the same thing.  Check the relative position of the bullets to the slide release tab that is folded over and horizontal.  It is supposed to hit the magazine follower when the magazine is empty.  But, if the cartridges are forward sometimes the bullet can hit the release and move it.

[Dand]

Chipster,  thanks for the suggestions and links in the other posts.  You've given me some stuff to consider.  I was using FMJ ammo.  I also tried some Speer Gold Dot ammo and when I whacked a magazine of that into the gun, the points would end up pointing down and the case base up, jamming the slide open.  I was often only putting 5 rounds in a mag. Maybe with a partial load there is enough movement of the rounds that I get them bouncing against the slide release.  I was having a little trouble getting the speers to set all the way back in the magazine.  I have a mag loading tool coming that might  help - easier than pushing them in with my fngers.

At any rate, I don't think I need to slap the mag so hard. Just need to make sure a little fold of my gloves isn't blocking the mag from seating fully.

thanks for the help.

[Dand]

I just got a note from Walther.  They want me to send the gun to them for inspection and possible repair.  Just to be safe I think I will even though I hate to have to wait to use it.

On another note. I just got dies and components for reloading the 40 from Midway.  Even to Alaska they mail stuff REALLY FAST.  Now, why did I forget to order some ammo boxes?

[Rock_Steady]

Most handguns that I have had the good fortune to work with will do that - I've seen it happen on everything from a Beretta 92 to an XD.  I really don't think you have anything to worry about.  Have a gunsmith look at your slide stop and see if he thinks its damaged - if not, you're cool!

[Captain38]

Having the slide run forward and chamber a round without any additional effort on your part when you vigorously insert a magazine is common and is a PLUS, NOT A MINUS as you've eliminated one extra motion altogether! 

You'll hopefully always press-check or otherwise verify a round HAS chambered but, either way, having the slide act on its own is ever bit as likely to put one in the spout as if you INTENTIONALLY caused it to move forward. 

Actually, most instructors now teach using the weak hand to pull the slide to the rear rather than using the slide release anyway.   The part you call a slide release is often called the "slide lock" instead and is meant to be used only lock the slide to the rear when loading and/or to indicate the pistol has completely run out of ammo.