Magazine insertion releases slide lock - is this bad?

[patentnonsense]

I've recently gotten a used Bersa 380 and a Megastar 10, and with both:

when I'm at slide lock and I jam a new magazine in, the slide will often close WITHOUT me touching the slide release. Neither tends to release unexpectedly otherwise.

This is convenient for faster reloads, but is it safe?

I don't know if this is due to wear on the slide stop, or deliberate modification, or what. Both seem to be fairly young guns, and not obviously worn in the slide stop notch. The Megastar 10 has magazine disconnect, if that's a possible factor.

Thanks!

 

[FunYet]

I had the same problem with a Kahr PM9. It turned out to be a problem with a worn/boken follower.

 

[natedog]

Run a search. What it is is the force of the magazine being slammed in causes the slide to move back just a little bit, but enough to release from the slide lock lever. Usually it happens with polymer frame guns more than steel. Almost every Glock, USP, and XD I've seen will do it.

 

[1911Tuner]

Mag Slam Slide Drop

There are some IPSC and IDPA shooters who would pay big money if a smith could make their pistol do that trick every time.

Check to see if the slidestop is fully engaging the next time you shoot the
gun to slidelock. If it's just partially engaged, the mag slam will cause an
inertial release. Pistol moves up...slidestop fights to stand still, as per
Newton's 2nd law...Wham! Slide goes to battery.

If that's it, try to determine why. First two suspects are a burr on the stop or slide and a weak mag spring. Could also be the magazine follower.

If it fully engages, look for signs of wear between the engaging surfaces on the slide or the stop...or both.

Luck!

Tuner

 

[mete]

Some guns are actually designed to do just that.

 

[BWC]

It is a common, if occasionally inconsistent happening on the HK USP series pistols. I have a USP45 and I like don't find it at all unsafe, and my pistol is consistent with it happening if I "slap" the magazine in. With a slower/easier insertion, it won't release the slide.

 

[Dr.Who]

My G17 or Colts have never done that, and I shoot IDPA. I would be concerned if mine did. That is why there is a slide release. If ith slide moved and I did not push the button or modify it to do so. Something is worn or broken and needs to be addressed. A gun that comes off slide lock without you hitting the button, is not safe in my opinion. It could be a step away from a slam fire (a maintance issue, dirty firing pin, etc)....

 

[Ivy Mike]

my brand new CZ-75 did that on its first trip out to the range. It scared me at first, but after careful examination and a few hundred rounds, it didn't do it again. In my case, I'd just suspect break-in bugs.
I have seen this happen to people who feel the need to slam magazines in. A good strong push is all you need. Don't beat on your guns if you don't have to.

 

[NMGlocker]

My Glock 17, Walther P99, H&K P2000, and 2 H&K USP .45's have done the automatic slide drop since day 1.
No safety concerns, all new parts, and it's not a maintenence issue.
I like the added speed it gives my reloads.
YMMV

 

[1911Tuner]

Who?

'Twas said:

A gun that comes off slide lock without you hitting the button, is not safe in my opinion.

I'd agree to that 100% if it was slippin' off the stop and goin' to battery
by just breathin' on it...but a mag slam is a pretty hard knock, and things move. I DO agree that it should be fixed, though. It's not supposed to work that way.

And:

It could be a step away from a slam fire (a maintance issue, dirty firing pin, etc)....

No moreso than letting the pistol feed and go to battery by tripping the
slidestop. Mechanically, the two operations are identical. There is the
matter of the gun going to battery unexpectedly and before the shooter
has the muzzle pointed in a non-lethal direction though...That could be bad JuJu for sure.

Cheers all!

Tuner

 

[Zach S]

When I SLAM a mag home in my Kimber Polymer or my Colt 1991, it does that. My Kimber more than my Colt, although my Kimber may not do it since I've replaced the extended slide stop with a standard part. Seems like my Kimber has always done it, my Colt has only done it about half a dozen times.

I dont think anything else I own has done it.

 

[horge]

http://www.thehighroad.org/showthread.php?s=&threadid=73729

http://www.thehighroad.org/showthread.php?s=&threadid=54816