S&W M&P9 question.

[Sunman]

I am hoping that some of you may be able to shed some light on, or confirm my situation/issue.

I have a Smith & Wesson M&P9 that I bought as part of a range kit brand new. I have fired exactly 429 rounds through, with 5 different types of factory ammo. 0 FTF, 0 FTE, 0 FTC. Basically it runs everything I can feed it so far. Here is my issue, if it even is an issue. Something new is happening, that never happened on my first 2 range trips. On my last trip with a friend, and when he was shooting my gun, on an empty mag, the slide would lock open as expected, when he ejected the empty mag and inserted a fresh full mag, the slide would fly forward WITHOUT him using the slide release. At first I thought he just had a finger on the release, (he is a lefty). But when I was shooting it, it happened twice to me as well. Each time it picked up and chambered a round and was ready to go.

Now, I am not sure if this is a design thing, or just an anomaly. I do strip and clean my gun after every range outing, so you can assume it is clean. Has anyone else experienced this? Is there cause for concern? After the first time it happened to me, I was checking the slide stop to make sure it was all the way up, and not just barely catching the slide, and it looked good to me.

Any help most appreciated.

 

[bollox]

Mine does it 100% of the time if you hold the grip at a 45 degree angle.

I don't think they "designed" it that way but rather I think it's due to the relatively heavy weight of the slide stop and inertia.

Personally, I would rather it didn't do it.

 

[Canadienseloco]

Mine does it. I like it. Shaves a little time off of slide lock reloads.

 

[Tengoo]

Yes, this is a common occurrence with M&Ps. Unfortunately the 'auto slide release' isn't very consistent and can give you a shock when it happens.

 

[Still alive]

Seen it happen also. Originally thought it was a specific mag problem but it happened with all 3 mags. The issue comes and goes. Hasn't happened in a while!

 

[Cb750k]

Doesn't happen with my m&p9, but I've only put 350-400rds through it so far.

 

[notsorichguy]

I have owned 9 M&Ps.... In 9, 40, 357 sig and 45.

All of them did it.

It is actually a designed feature in the M&P line.

 

[krausb]

Doesn't happen with my m&p9, but I've only put 350-400rds through it so far.

They all do it. It just depends on how forcefully you insert the fresh mag.

 

[Still alive]

I have owned 9 M&Ps.... In 9, 40, 357 sig and 45.

All of them did it.

It is actually a designed feature in the M&P line.

Then why doesn't it happen all the time a loaded mag is inserted? Is there a magic move to make it happen and one to not make it happen that we don't know about?

 

[ez8]

normal, slam it in and it will slam forward.
you have to really slam it in and then it will do it.

 

[loonz84]

Its a design future. My 9 and .22 do it . Only way to avoid it is gently place mag in. I like the feature personally!

 

[Cb750k]

They all do it. It just depends on how forcefully you insert the fresh mag.

I'll have to slam a few home next time I get out shooting and see if it does it.

 

[Ganderite]

I have a 9, a 40 and a 45. They all do it, almost all the time. I count on it when shooting against the clock. If yours does not, you are not seating the loaded mag hard enough.

 

[fdc]

I do this intentionally with mine when shooting defensive pistol and IPSC. Time saver for sure.

 

[onetwentyish]

I remember reading about this and have seen some youtube vids on it. Seems it has been chaulked up to the polymer frame flexing when afresh mag is slamed all the way home fairly hard.

 

[enefgee]

The "trick" to it is that your loading hand (off hand) has to move upward at a 45 degree angle to the grip centre when slamming the mag home.

 

[Punisher-One]

It's not a "design feature" it is a polymer framed pistol with a heavy metal slide on the top of it. I can do this on my M&P, have done this on numerous Glocks, and happens frequently on my PX4 duty pistol.

 

[hawkmp9]

I believe it is actually a design feature for the slide to release its hold open feature when slamming on inserting a new mag with enough force. If it was not a design feature, the slide would remain open and, if it did not, then it would be a malfunction for it to do so. When taking a smith and Wesson m&p course this feature is explained to an individual.
Some magazines wear out to the point that they do not hold open the slide on the final round.

Keep in mind it is a duty pistol.

 

[gixxer75]

Normal for mine as well, every time I slam in a full mag the slide releases.

 

[enefgee]

It's not just polymer guns that do this, the M9 pistol does this as well.