Light primer strikes in the M&P 9's

[Tokarev]

Here is the follow up. Called S&W customer service, described what was going on, and said I did not want to send the pistol back since I had matches pending & liked the set up as, is no upper switching please.

Rep asked me if I knew how to change the striker assembly and my address, two days later one shows up in the mail no charge and she has run perfect ever since. Running the new striker dry and it is smoother than my old one lubed.

Boats

I have had the some light strikes with my M&P 9 also. Wish I had thought to call S&W, instead I ordered xtra power wolf striker spring, striker channel from SSS last Sunday. But , then again it has not showed up yet. Maybe I still should call S&W.

Gottem today, now for the installation. Thanks Kenny.

Please let us know how the new spring works!

[Boats]

That quote of mine was end of March, Since 4 matches with the M&P two light strikes total. It's not fixed. I am pretty sure it's spring rate. Am committed to the gun through the Carolina Cup end of June. After may send it to a good S&W man.

Boats

[mwx40x40]

Here is the follow up. Called S&W customer service, described what was going on, and said I did not want to send the pistol back since I had matches pending & liked the set up as, is no upper switching please.

Rep asked me if I knew how to change the striker assembly and my address, two days later one shows up in the mail no charge and she has run perfect ever since. Running the new striker dry and it is smoother than my old one lubed.

Boats

I have had the some light strikes with my M&P 9 also. Wish I had thought to call S&W, instead I ordered xtra power wolf striker spring, striker channel from SSS last Sunday. But , then again it has not showed up yet. Maybe I still should call S&W.

Gottem today, now for the installation. Thanks Kenny.

Please let us know how the new spring works!

So far , so good. I ran 150 rounds through yesterday with no problems. More rounds will be needed to know for sure, but this is a good start. The Wolff extra power spring was noticeably longer than the original and I was concerned about it afffecting the trigger job that Dan Burwell did on this gun. The trigger to me still felt good. So if it added anything to it , it was small.

[Boats]

Match last night two light strikes in 60 rounds. My buddy's M&P same match using the same handloads no FTF It's getting mailed off after the Carolina Cup.

Boats

[Tokarev]

Match last night two light strikes in 60 rounds. My buddy's M&P same match using the same handloads no FTF It's getting mailed off after the Carolina Cup.

Boats

I saw on another board that S&W was "upgrading" the triggers on Atlanta PD's M&P's. Since I doubt most reporters know the difference between a trigger, a front sight, and a striker could it be some kind of light primer strike problem?

Click on left to watch video

[jasmap]

Match last night two light strikes in 60 rounds. My buddy's M&P same match using the same handloads no FTF It's getting mailed off after the Carolina Cup.

Boats

I saw on another board that S&W was "upgrading" the triggers on Atlanta PD's M&P's. Since I doubt most reporters know the difference between a trigger, a front sight, and a striker could it be some kind of light primer strike problem?

Click on left to watch video

That was my immediate guess when I saw that. I doubt they really knew the difference.

[kend]

I saw on another board that S&W was "upgrading" the triggers on Atlanta PD's M&P's. Since I doubt most reporters know the difference between a trigger, a front sight, and a striker could it be some kind of light primer strike problem?

Click on left to watch video

Naw, it was a pin in the trigger that was backing out, no performance problem but they didn't like the feel of the trigger like that. S&W sent some guys down and went through all of their S&W pistols, M&P's or not, and corrected anything that needed it. No recall on M&P's, it was an isolated incident according to my source at S&W.

[Boats]

I take the M&P to a nearby clubs pin shoot today. No primers to load and hoarding my factory ammo for the Carolina cup. Cleaned out every thing I had ammo wise loaded 5 mags with a mix bag of 9mm. 124 gr lead with W 231, 115 Gr factory WWB & PMC, and some 115 gr plated loaded with Clays and small pistol mag primers. no order or sorting just filled the mags

Also cleaned the M&P including the striker, and put the factory mainspring back in. It ate them all without a hickup.

Go figure.

Boats

[Tokarev]

Naw, it was a pin in the trigger that was backing out, no performance problem but they didn't like the feel of the trigger like that. S&W sent some guys down and went through all of their S&W pistols, M&P's or not, and corrected anything that needed it. No recall on M&P's, it was an isolated incident according to my source at S&W.

I'm guessing the center pin that acts as the pivot point? This pin has backed out a little on my .45. It actually backed out early on but doesn't seem to be getting any worse.

[Boats]

Question for you guys, Does the mainspring have anything to do with the strikers impact on the primer. I know on a 1911 there is no connection between mainsping and how hard it hits a primer. On a S&W double action revolver it has everything to do with primer detonation.

What about the M&P does a lighter mainspring effect the striker ?

Boats

Edited June 15, 2009 by Boats

[scheirere]

Boats,

Yes and no. Not directly anyhow. However, like any striker fired pistol, there needs to be a balance between the main (recoil) spring and the striker spring. If the striker spring is too heavy compared to the main spring, then the slide may not be in battery when/as the trigger is pulled. This is a well known situation with Glocks, especially when they are tuned to run in USPSA/IPSC competition. As the main spring "wears out", the slide starts to move out of battery when the trigger is pulled. The result is that some of the striker's energy is used up pushing the slide/barrel assembly back into battery and you get a light strike on the primer. In escence, it's similar to having a high primer.

[Boats]

Thanks

Wonder if that's me ? I use a lighter mainspring and non captured rod. It won't cycle my hand loads properly with the factory spring. Will find out soon as it has to fire about 300 rounds of factory ammo using the factory spring & captured rod. this weekend. From your description can see how a weak mainspring could have effect.

Boats

[ryan45kim]

That big spring that runs underneath the barrel is a recoil spring.

A mainspring in a 1911 is inside the mainspring housing right below the grip safety.

You’re mainspring has a lot to do with ignition on a 1911; it is what drives the hammer forward. It also pays a part in controlling the slide unlocking.

The striker or firing pin spring (I’ve seen them called both) goes around the striker/firing pin in glocks and m&ps. It drives the striker into the primer, so yes it has an effect on ignition.

I’m just not sure what question you are asking. Are you talking about recoil springs or striker springs effecting ignition.

[Boats]

Recoil

Have been running a lighter Recoil spring than factory, wonder if it has anything to do with ignition. I don't think so but ?

Boats

[Dan Burwell]

Recoil

Have been running a lighter Recoil spring than factory, wonder if it has anything to do with ignition. I don't think so but ?

Boats

I am not a fan of the light recoil springs in the M&Ps. You will get light hits with them sooner or later. What will happen is the recoil spring will not return the gun fully into battery due to the imbalance between the striker spring and the recoild spring.

if your hand loads are not cycling the gun turn them up, that is why most of us reload... so we can tune the ammo to the gun. Tuning the gun to the ammo will usually lead to issues sooner or later.

[Boats]

Dan I agree with you on tuning the ammo to the gun not the other way around. Problem with this M&P 9L is it won't cycle 100 % with fairly hot re-loads. Factory WWB Factory spring cycles OK. Reloads are store bought 124 gr LRN with 4.4 of W 231 That's a max load in some manuals and crono's out of the 9L at 1135 fps average, 141 PF.

Now it's not impossible my handloads that did not cycle with the factory spring had inconsistent powder charges instead of the charge being too light. What with the component shortage I don't have any good options to experiment with hand loads or alternate factory for that matter .

I may double check all charges throwing and weighing with a hundred or so reloads after the major match I am shooting this weekend. It's 14 stages and I have enough Factory WWBox to shoot the whole match have put the Factory spring back in. That with a clean dry striker ought to be a good test.

Thanks all for your thought and advice

Boats

Edited June 18, 2009 by Boats

[ryan45kim]

Boats sorry it took so long to respond, it’s been a busy week.

In striker fired guns the recoil spring and the striker spring are working against each other.

The recoil spring is trying to close the slide and keep it closed, while at the same time the striker spring is pushing on the slide in the opposite direction.

This system works because the recoil spring overpowers the striker spring.

If you start weakening the recoil spring without balancing the striker spring you can induce a multitude of problems, among them are premature unlocking of the slide and barrel, or the slide and barrel not fully closing.

Either of these conditions can cause light strikes.

I normally run a P-16 in limited and my favorite recoil spring I ever ran was an ISMI 9lb spring.

I stopped running a 9lb spring because I could not get it to run reliably.

[Boats]

Ryan

Makes sense. I have the factory spring in now shooting factory ammo. Will see how it runs.

Boats

[Boats]

Posting twice same M&P two problems. Striker Fired every cartridge at the Carolina cup. One stage failed to extract and jammed up good causing a DNF on that stage.

Shooting something else for a while You guys figure this out let me know

Boats

[Filishooter]

The recoil spring is trying to close the slide and keep it closed, while at the same time the striker spring is pushing on the slide in the opposite direction.

This system works because the recoil spring overpowers the striker spring.

If you start weakening the recoil spring without balancing the striker spring you can induce a multitude of problems, among them are premature unlocking of the slide and barrel, or the slide and barrel not fully closing.

Either of these conditions can cause light strikes.

This, along with Dan's input is what I think is happening to my Pro. Attached is my reply to Dan when he mentioned that its probably a weak recoil spring on the M&P forums.

I DO think I either have a worn recoil spring and/or its not strong enough. Looking closely when I dryfire, I see a little movement in the slide, it moves very-very slightly to the back as the striker is being prepped. You can barely notice it, but it does move. Then the slide moves slightly forward when the striker falls. I think this could be enough movement to cushion the strike! I got my new parts today, I'll post an update when I test it out.

FWIW, this problem (intermittent soft hits) just started happening. I have about 5000+ rounds through the gun, It had been working fine with the 13lb spring and my reloads until this month. My reloads are a decent 132PF. I would suggest anyone running a 13lb spring to change it out more often. I think 13lbs is right at the limit of proper function, when it weakens slightly you may have problems, where a factory spring will probably still have enough energy even when worn. I'm probably going to move up to a 15lb. I guess I'll have to do some timing drills!

Edited July 9, 2009 by Filishooter

[jkatz44]

My dept issues M&P 9's (and some 9c's) and we have seen some issues with Winchester NT frangible ammo. My issued m&p would only fire approx 1 in 5 the other day. After much consultation with Smith, we believe the problem may be ammo related, specifically the primers...sent a buch back to Winchester to be evaluated...

Colin

PS, replaced my striker spring and she runs fine again...even with the NT...who knows.

where can i get a stiker spring

[mwx40x40]

My dept issues M&P 9's (and some 9c's) and we have seen some issues with Winchester NT frangible ammo. My issued m&p would only fire approx 1 in 5 the other day. After much consultation with Smith, we believe the problem may be ammo related, specifically the primers...sent a buch back to Winchester to be evaluated...

Colin

PS, replaced my striker spring and she runs fine again...even with the NT...who knows.

where can i get a stiker spring

I got mine from Speed Shooters Specilities and my light strikes went away. Check with Kenny he is in the BE Dealer section.

[jkatz44]

My dept issues M&P 9's (and some 9c's) and we have seen some issues with Winchester NT frangible ammo. My issued m&p would only fire approx 1 in 5 the other day. After much consultation with Smith, we believe the problem may be ammo related, specifically the primers...sent a buch back to Winchester to be evaluated...

Colin

PS, replaced my striker spring and she runs fine again...even with the NT...who knows.

where can i get a stiker spring

I got mine from Speed Shooters Specilities and my light strikes went away. Check with Kenny he is in the BE Dealer section.

i don't know if my misfires are do to high primers or light strikes