just purchased about a 4 month old sw 40 from an individual for a great deal and took it to the range today, shot nice, accurate and tried various ammo as i always do to make sure it will eat most anything you put through it, including corbon, speer gold dots and so forth. One thing that i noticed after the first mag was the slide release did not seem to function as most other semi autos. when a mag was empty the slide will remain open, replace mag and press mag release button and it would not just release the slide. I had to push the release button and pull the slide back just a little before letting it go and it would release and be ready to go. IS this common for the m&p pistols? this is the first one i have ever owned and i know my sigs, glocks, h&ks and taurus's do not function this way. Thanks in advance for any input.

My M&P9 is the same way. I rarely use the slide stop as a slide release though. No need to depress the slide stop if your going to pull the slide back anyway. This is called the "slingshot" method. As soon as you pull the slide slightly rearward, pressure on the slide stop is relieved and it will drop down out of the way. Just pull the slide back and let it fly forward. Do not "ride" the slide forward, let it fly!
IIRC, this is the method shown in the owners manual too.

Slide stop vs. slide release....and age old argument.

IMO, the slide releases are pointless on the M&Ps. I just slingshot both of mine.

Sometimes the stop notch in the slide is rough or angled to steep to allow the lever to slip off easily. A small file can clean it up easy enough.

My M&P .40 was the same way when first purchased. After a few hundred rounds fired through it, the slide release works fine with just the thumb operation.

It's a slide stop, not a slide release. You should sling-shot the slide after loading, or slap that mag in hard enough that it "auto-releases" instead.

It's thin sheet-metal and if you use it as a slide release, it won't take long to wear down and then fail to work properly.

My M&P has forced me to use the slingshot method (which isn't a bad thing). I will admit, if someone offered an extended lever (a la Glock, which is what I was used to) I'd grab it.

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