Is this a common problem?

[rack&roll]

I just noticed that my approximately 1&1/2 year old M&P 9L isn't locking the slide back after the last shot anymore. I rarely, if ever, shoot to slidelock in a match so I'm just now noticing the problem. (shows how much I've been practicing with this gun) I keep my gun & mags very clean, so it's not dirt or residue. I would say the gun has less than 2000 rounds through it, and is shot infrequently. There are no other issues, it is very reliable otherwise. Anyone else have problems with their 9L's or Pro's not locking the slide back after the last round?

[dcarter]

It is not a real issue. It is probably your mag springs getting weaker. Your mag follower is what pushes up on the slide stop after the last shot. If the spring is weak or your slide stop worn down on the edges it may cause this to happen. If it bothers you I would trade out the mag springs first. If it doesn't and your pistol is working fine otherwise I would leave it alone. If you start having feeding issues look at your mags first.

[beastfrog]

Could be the follower. The latest followers are grey and have a 9 imprinted on them. Does it do this with all mags? or just 1 or 2? I have a couple of mags that do this but the ones with the newer followers don't.

Edited December 9, 2010 by beastfrog

[want2race]

I had the same thing, thought it was mag springs. I cleaned the tubes and followers and that fixed it for me. It usually one or the other (dirty or worn springs).

[Dan Burwell]

Any chance your thumb is on the slide stop?

It happens to me all the time when I test fire guns that have a small back strap on it, that is just where my thumb likes to sit. With a medium it only happens occasionally, the large never. You guessed it my own gun has a large backstrap

[G-ManBart]

It can also happen if your ammo is on the light side. The 5" M&Ps have a heavy slide compared with other similar guns (i.e. G34) and they can get picky if the ammo is under 135PF...again, not all guns, but some. R,

[rack&roll]

Thanks for the tips. Springs are still good. (Less than 2000rds.) My ammo IS on the light side, and it's probably a contributor. Also, I do use the small backstrap, so I might be hitting the slidestop. My mags are older ones, too. I'll clean the mags, do all the other things and report back next time I'm at the range. (Might be awhile, I've been using my new CZ Shadow Custom lately.)