Took my new M&P-9 (Serial # DTC96**) with ambidextrous safety shooting for the first time yesterday.

Within the first 100-rounds my groupings started to go right from point-of-aim. I could literally see my front-sight post progressively sliding to left in the slide's dovetail.

Shortly thereafter the front sight was way left. After clearing my M&P, I braced the slide against the wooden bench and tapped the slide with my hand, the sight went all the way to the right, turning the slide around I tapped to get the sight centered but it slid right out of the dovetail to the left and out onto the floor. Hmmmmmm...

Figuring this could just be an issue with the sight, having a set of new factory night-sights on hand which I planned on installing when I can afford the sight pusher (along with the Apex duty package), I tried the Trijicon marked sight and could slide the front sight in almost fully using only two fingers. I then braced the slide and sight against the bench and tapped the slide by hand to center the front sight post. Needless to say, I could shoot tight groupings all day long with the M&P, provided the sight wasn't drifting out on me and it is a real pleasure to shoot - I love the gun, but this issue is of course a concern as far as QC is concerned.

I now have two useless front-sight posts (factory white dot and tritium). I think as the slide warmed up from the shooting (just over 300-rounds total - for the day - of Lawman 115gr FMJ, but issues showing under the first 100-rounds) the dovetail was opening and the recoil assisted the sight in drifting. Both front-sight posts appear to be consistent in their sizing, so the dovetail may be too large.

Has anyone else experienced this issue?

I am waiting to hear back from S&W Customer Service to resolve the issue, needless to say it was disappointing to experience and see the issue... but alas, rather on the range than in a gunfight.

She shoots better than my GLOCK22 and I plan on purchasing both an M&P-40 and M&P-45 Mid-Size I like it that much, but have never ever had an issue crop up like this one from any other manufacturer.

My sister-in-law giving her a go on the range yesterday :

not on an M&P, but I have seen it on other weapons (BHP's, a SIG P220, a couple of rear sights).

Generally, if you degrease the slide and the sight and reinstall it with some locktite red, it stays put

Okay, I figured screw it and went ahead and installed the S&W factory V7-style Trijicon rear night-sight today along with the rest of the Apex duty package (the trigger action is so sweet now, so I'm sure I can tighten up on already good groups!).

Sorry the pictures are so ******, only have my iPhone available right now. Now if I can get the front sight issue resolved, apart from a few more magazines and Arredondo magazine extensions and a grip stippling job from Boresight Solutions - I'll be a very happy camper.

On my FS9 I had the opposite condition.

Mine was so tight I thought I'd have to get a sight tool.

Very happy with Hi-Vis fiber optic.

I've heard of this before with the M&P. It's easy enough to fix and S&W will fix it up for you no problem.

On a lighter note..can we have better pictures of your sister in law

It happened on mine and i just got it back from S&W. I have the 5 inch Pro and it was the fiber optic front sight that was loose. Also another vote here for more pictures of your sister in law.

You will probably get a new slide. The dovetail is too big. Don't screw around - just overnight it back and they will get it right back to you.

You guys are siiiick and eviiiil! I DO appreciate that! *LOL!*

My sister-in-law is very pro gun, an attorney and a now a JAG with the ARNG... and yes gentlemen, she is single. *s*

shawn mccarver : Copy that, will do. Thanks brother!

Pro gun, JAG, Single and an adorable little blonde? Sounds perfect!!

I am in love!

I recently bought the M&P 9mm Pro Series. It was hitting between 2 to 3 inches right. I could easily see the front sight was not centered. It favored the left side of the slide in the dovetail. I measured the position of the sight for my notes and then drifted the sight to center it.
Returning to the range I was hitting on target where I expected. But while shooting 2 boxes of ammo things changed. The front sight was once again off center. And once again favoring the left side. It's obvious the front sight is loose and does not stay in place under recoil. While I suspect I could very well just add a drop of glue and then center the sight again, I'll return the gun to the dealer and ask him to contact S&W and go from there.

The pistol was returned to the dealer April 16 and I just got it back today May 13. A letter inside the case says the front sight was replaced.

I had the same problem on my 9mm Pro...called S&W, they sent a call tag and all is good. Another friend of mine had the same problem and he removed the front sight, took a punch and made about 8 dimples in the bottom of the dovetail, then pressed the front sight back into place and all is well. Like he said, the only ay THIS sight is going to move is if I move it. He did mark where center was with a pencil and re-aligned it, was shooting center of mass with NO movement whatsoever!
Randy

In my case I could have fixed the sight myself, but I opted for a factory repair. I had to consider that I did not know what was wrong. The sight base could have been too thin, the sight base could have been too narrow. The dovetail might have been improperly cut. I had to consider I may install other brands of sights down the road. If I had an improperly cut dovetail, and I never resolved it, and I bought different sights, and they were loose too- well, you can see in that worst case scenario, a factory replacement of the slide would have been the proper fix.
I could have staked it, I could have glued it. I had pistol matches on the calendar and I was eager to see how well it would perform. But not knowing if the trouble was the sight or the slide, in the end I am glad I had the factory repair. Since the slide was not replaced, that tells me other sight options would probably be Ok when installed. I do have a favorite supplier of very good quality sights. And I will ask him what his experience has been with installing his sights on this pistol.
Al

Excellent shooting stance!

Actually I fired 50 rounds through my M&P9 9mm and the site fell off....
I was not too happy... I took it to the store where I bought it and the on duty gun smith tried to fix it... I went back home and fired it again another 24 rounds and the same thing happened...the gun smith is sending it back to have S&W look it over and repair it...

Just took my new MP9 FS w/ night sights and the watched the groups shift as i shot. the front sight post is nearly off the slide....sending it back to S&W ASAP!