I presently have 4 M&P's. 40, 9, 45 anmd 45C. On everyone of them when I insert a fresh loaded magazine the slide releases without me pressing on the slide lock. It seems to automatically release. Is this as designed or a flaw in the design. I am extremely satisfied with my M&P's. The M&P 40 is our department issue weapon. We went to it from the Beretta 96 and Glock 22. My next purchase will be the M&P Pro 9MM with the longer slide.

This is what is known as "auto forwarding" but usually occurs when the magazine is inserted forcefully but not necessarily all the time, some of my M&P's do it almost all the time especially if the gun is held at about a 45 degree angle and I slam a new magazine in and I have a fullsize 9 a compact 40 which does it almost all the time and a fullsize 40 which does the same, but not the M&P Shield40 but one of my 2 M&P 45's also some of the time will auto forward!

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59,M&P9,40,40C,357,(2)45,G26

So. is this by design? Or is it a malfunction?

If it was by design, then it should happen every time. But I wouldn't call it a "malfunction" either. It's a "feature" . My FS 9 will do it if I slam the mag in at a certain angle. Personally, I like when it happens, as it saves time getting ready to shoot again.

My full size 9 started doing this after I ran about a 1000 rounds through it and does it now almost every time I insert a fresh mag.

It's no big deal as long as the muzzle is pointed in a safe direction like it's supposed to be. A couple of my AR's auto forward when I go prone during a match.

My M&P's all will do the same if I insert the mag hard enough.

Actually it is not intended to "auto forward" and it may be random in some models for instance my Shield 40 does not do so, but my 9mm fullsize does so almost always.

Out of my 2 45's one will do it frequently and the other requires me to rack the slide. My M&P40 compact will auto forward occasionally, but my fullsize M&P40 almost without fail auto forwards.

It seems to me that with the right amount of force of inserting a magazine regardless of the angle although about 45 degrees seems to be when you notice it is when this will happen. If you do not like this then send t back, I myself like not having to take an extra step but do not rely on it to always happen!

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59,M&P9,40,40C,357,(2)45,G26

Doesn't anyone read the manuals anymore?

BWAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHAAAAAAAAAA!

They don't use the search function either.

I doubt if they ever even leave the case...

Bet most can't even find it either.... It's a bit tricky,but does work.

So for us that can't use a manual or a search, what does the manual say about this issue?

Just a little thing called inertia. Lots of autos do that. No biggie.

A co-worker of mine would say that the auto forward is a er, ahem, clue that you're inserting the magazine with excessive force.

Different weapons system, but I once saw a most manly mag insert in an M4 that resulted in the entire ammo load of the mag foutain out of the ejection port.

There is no need to slam the magazine into an empty weapon. Doing so greatly increases the chance of popping the top round loose and causing a double feed. As magazine springs relax a bit with wear, the probability goes up. I see this quite a bit with folks who confuse the force used to insert a magazine with sexual capability.