Problems with My New M&P9 Mags

[MusicMatt]

I just picked up my new M&P9 after work yesterday. When I got home I cleaned it and tried to insert one of my 10 round mags into it with slide closed - Not happening. Open the slide - No problem. I thought this may be an issue with just one mag, but it is all of them. The 10th round sticks up too far for the magazine to close properly on a closed slide.

After doing some research, I found many people complaining about the new followers being too large and you must dremel them down.

Not really thinking I should have to break out power tools on my brand new handgun to get proper operation.

Should I call SW about this? Will the springs relax and make this a non issue?

It loads fine with 9 rounds, but I shouldn't have to sacrafice capacity any more than I already do.

[shanesanity]

Can you shoot it with 10 rounds? Are you worried that it's not flush?

[MusicMatt]

The magazine will not insert all the way in with 10 rounds in it on a closed slide.

[Milsurps]

After doing some research, I found many people complaining about the new followers being too large and you must dremel them down.

Yup very comon with the latest suplied 10rnd S&W mags.
Normal capacity mags no issues.
Had to do this my 10 rnd mags. It does work.
No mod required to the gun.

[NorCal Einstein]

I would suggest you don't dremel anything yet. Load and unload the magazines a few times to get the spring working. You can also load them up to 10 and set them in a drawer somewhere for a day or two.

When I went to 10 rounders, I had a similar issue because the springs were really stiff and once you have the 10th round in, there's no additional "slack" in the spring when you try to drive it into a gun with the slide closed. I would load and unload a few times a day, and then let it sit fully loaded overnight. Within a week things got better and now there are no issues.

[shanesanity]

Hmm, I hope I don't have these problems with my new one arriving on the 12th :/

[NorCal Einstein]

Yup very comon with the latest suplied 10rnd S&W mags.
Normal capacity mags no issues.
Had to do this my 10 rnd mags. It does work.
No mod required to the gun.

Are "latest supplied" within like the last 6 months? Or a year or more?

[Zerorye351w]

I've not had a problem inserting the mag fully in my M&P VTAC 9mm, with 10 rounders, but it does take a lot more force than my M&P45. Haven't tried to rack the slide with the mag full, but I'll give it a test run tonight to see how that fares.

[Milsurps]

Are "latest supplied" within like the last 6 months? Or a year or more?

More like the last couple + years...

S&W Lawyers to thank I'd guess.

[GMG]

Yup very comon with the latest suplied 10rnd S&W mags.
Normal capacity mags no issues.
Had to do this my 10 rnd mags. It does work.
No mod required to the gun.

Thanks for posting this. I have a fairly new M&P 9c, I can't even get 10 in the magazine!

[timmyb21]

Slam it home a couple times, it'll catch. Don't need to baby your m&p, it can take it.

[Catalyst81]

I just noticed this a few minutes ago with my new m&p 9. I've left the magazines loaded for a few days. I'll try loading and unloading for a bit and see if that helps the springs before I resort to modifying anything.

[scootle]

I wouldn't be so quick to Dremel anything on a new gun... lol. The stiff 10th round is normal thanks to the lawyers. God forbid you should somehow manage an 11th round stuffed into the mag when it loosens up over time. BTW, this is not a problem unique to M&P... it happens on many different systems depending on how the mags are blocked.

My M&P9 is going on 2 years old now and 10 rounds on a closed slide is still something I have to double check to seat properly. If you get an UpLULA to help you load the mags, the 10th round is a lot easier to get into the magazine itself, btw. If you are taking a training class and don't want to be bothered with worrying about improperly seated mags during "tactical" reloads, just run spares with 9 rounds to give them a little more breathing room. It's not the end of the world.

[MusicMatt]

Went home and was able to closed slide a mag with ten rounds in it. It took some force. I think I will put a couple thousand rounds through the mags first to see if they loosen up and take care of the problem.

[kf6tac]

I'd definitely recommend putting the mags through a couple cycles of loading and unloading to loosen up the springs, as others have suggested. You can also try compressing and decompressing the spring with a speedloader to save yourself the trouble of actually loading and unloading rounds.