Light primer strikes in the M&P 9's

[Boats]

Am about 6 months into a couple of M&P's one a 9L other 9C plus my shooting buddy has a 9Pro. Between us we have had about half a dozen light strikes that failed to ignite the primer. This is all club IDPA shooting. No telling how many rounds it took to get 6 light ones, thousands I guess.

My guns use WWhite Box for matches and my own reloads for practice, although lately because Wal Mart has been out of WWB have used the reloads for match work. Have taken the strikers out cleaned. ran with and without oil on the firing pin and striker too. No burrs or hangs on any of the moving parts. While all ammo can fail at times and dirty strikers will cause problems. Have come to the conclusion the M&P is a light strike gun.

Am familiar with fast hammers and light strikers, my Single Shot Target Rifles are speed locked with light hammers and tweaked springs. One fails and it's not a negative in those matches plenty of time to re-load. IDPA it cost to have a FTF and is not acceptable. The mechanics are not real complicated either a heavier pin or stronger spring ought to cure the problem. I may have missed something but don't think so. I should also say have seen Glocks do the same thing light strike and FTF but have never taken one apart or worked on a Glock. I think the striker design is similar both pistols.

Anybody sell aftermarket striker springs for M&P's ? I can't see any way to tweak the pin itself.

Boats

[almostold]

I've had the reduced power Wolff striker spring in my Pro since June and shot thousands of rounds through the gun with no light hits. i polished the striker and used Slide-Glide (lite). I have read other posts that say to keep several striker assemblies on hand?? Maybe give Dan Burwell a call. I have also learned from my days with the CZ that a 'hard seated' primer is the only way to go - assuming reloads are causing most of your problems.

[G-ManBart]

Did any of your light strikes come with the factory WWB?

I'd keep the striker, spring and tunnel totally oil/grease free. We've had problems with light strikes on Glocks that people got oil into the striker tunnel. It stayed in there, got thicker and combined with powder/primer fouling and eventually the guns stopped working. Obvioulsy, it's not the exact same design, but close enough that it's worth trying.

The state police here issue M&P's in .357 Sig and I haven't heard of any problems with light strikes, but I'll ask the instructors that I know. R,

[Boats]

Most of the light strikes came from Factory WWB. I also use the exact same hand load and WWBox in a BHPower and never had one fail to fire, of course the mass in that Browning's external hammer is a lot more than the M&P's more modern design. Glock at our club did the same thing couple of matches ago. Shooter was not real experienced with home remedies. Guys took it apart for him and inside the striker was oily with built up brass residue. I am sure running dry is better not allowing residue to build up but the striker works so much smoother when lubed. Anyway have tried both. Running the M&PC Dry and M&P9L lubed but frequently cleaned.

6 light ones in several thousand rounds is not a lot. And may well come from the ammo anyway. My experience has been that heavy hammers and strong springs make cartridges fire every time. I shoot some rifle matches for old Military rifles, never had a 03 Springfield or Trapdoor 45/70 fail to fire. But who would shoot targets with those heavy hammers unless the match is restricted to similar guns. Remington 700's with internal strikers will fail to fire surplus 308 frequently. I was selling one to a guy that had a Titanium pin once. He tested it with cheap surplus ammo misfired half the time, put the factory pin back and it popped most of the time.

Don't like to rule out something that I have not considered or seen but am pretty convinced it needs a stronger striker spring.

Boats

Edited February 21, 2009 by Boats

[Duane Thomas]

Years ago a very good pistolsmith told me two things I have never forgotten: "Whenever a gun malfunctions, people never blame the ammo; they blame the gun," and "Whenever an otherwise 100 percent reliable gun malfunctions, the first question you should ask yourself is, 'What did I change?'"

We get a lot of questions on here that, bottom line, break down to, "My gun only malfunctions with X ammo, it's totally reliable with everything else, what should I do to my gun?" Answer (IMHO): don't do anything to the gun. Quit firing that ammo. Problem solved, 100 percent reliable gun.

[Sarge]

My PRO has never failed to fire. But I have never fired WWB. Remington UMC and reloads go bang every time. It did fail to load once If I remember right.

[mike cyrwus]

there is often a buildup of brass shavings and crud on the inside of the channel against the breechface. that, and keep the channel dry. Also check that the striker guide isnt cracked.

[Sarge]

Then again I really believe in clean guns. I clean mine every time I shoot it. I spray gunscrubber in the striker and then blow it dry with a compressor. A lot of crap comes out of there usually.

[High Lord Gomer]

More than 50,000 rounds spread across 6 M&Ps (9, 9c, .45, and 3 .40s) and I've never had a light primer strike in any of them. I went over 30,000 rounds through the M&P9 before I even knew how to take the striker assembly out to clean it. I did have the mag drop problem with the M&P9c, but they fixed that and it worked well until I sold it.

[FLG8R]

I was having similar problems with my M&P .40cal. Started when I was shooting with reloaded ammo, or at least that was what I thought. Usually I would shoot WWB, and never had a problem, so I switched back. But sure enough I started having light strikes again. After this started happening with more frequency, cleaning the entire pistol, striker channel and all, I finally called S&W. They asked me to send the pistol back, free of charge, and a few weeks later they sent it back. Basically they send me an entire new slide/upper The work slip sent back with the gun gave no further explanation so I called them back. What the service person bascially told me was that it was easier to just replace the entire upper for the company than it was to troubleshoot the problem. Plus they sent it tp me with another high cap mag. Since then no problems with the pistol shooting with either WWB or reloads. So no real explanation but the gun runs now...mysterious

[Boats]

Thanks all for the comments, This is what I plan to do. Buy a couple of striker & pin assemblies from S@W just in case I screw something up. Polish up real good looking for minimum drag. Also polish the inside of the slide were the spring rides, something I have not done so far. Run them dry from now on and pay particular attention to keeping the pin and all real clean, blast from air hose every time. I did check Wolf's site, they have lighter striker springs to reduce trigger pull but not stronger ones. They say the factory spring is 5 lbs and offer 4s as an alternative.

It could well be ammo but am not changing my ammo routine of WWB & hand loads. WWB is a given and don't know any good way around it. I will pay particular attention to primer seating. Don't think it's a problem but you never know. Hand seat using a Lee tool, if anything feels "off" toss the shell.

Boats

Edited February 22, 2009 by Boats

[Boats]

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

[Sarge]

Knew it had to be some piddly thing like a bad part. The M&P is a good gun for what it is. Good luck and hope it works for you. Come back later this summer and let us M&P guys know how it does.

Thanks

[mgood]

I was having similar problems with my M&P .40cal. . . .

I finally called S&W. They asked me to send the pistol back, free of charge, and a few weeks later they sent it back. Basically they send me an entire new slide/upper The work slip sent back with the gun gave no further explanation so I called them back. What the service person bascially told me was that it was easier to just replace the entire upper for the company than it was to troubleshoot the problem. Plus they sent it tp me with another high cap mag. Since then no problems with the pistol shooting with either WWB or reloads. So no real explanation but the gun runs now...mysterious

I just told this story in another thread.

I have an early model Sigma SW40F .40 cal. Maybe once every one or two hundred rounds, I'd get a strike that would dent the primer but not fire the round.

I mentioned this to a gunsmith. He took a look at it and told me the slide wasn't fitting correctly.

He sent it back to Smith. They replaced the slide for free and returned it with a couple of new mags. None of this cost me a dime.

I've put about 1000 rounds through it since (about 2000 rounds total) with no further problems.

The M&P design seems pretty similar to my Sigma. Take that for whatever it's worth.

[G-ManBart]

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

Were you able to see any difference between the old and new strikers?

[Boats]

I looked carefully at the new striker compared to my M&P9L and 9C both. I think they are identical but, the new one feels smoother pushing on the spring with my thumb. Springs being what they are I expect I just had a bad one.

Boats

[Tokarev]

I looked carefully at the new striker compared to my M&P9L and 9C both. I think they are identical but, the new one feels smoother pushing on the spring with my thumb. Springs being what they are I expect I just had a bad one.

Boats

Any further problems with your gun?

I have just started shooting my Pro and I've been getting light primer strikes.

Does anybody know of a source for a +P striker spring? Wolff makes a reduced weight spring but I don't think that'll help my problem.

[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.

[Tokarev]

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.

Did you order the extra power spring directly from Wolff? I don't see anything other than reduced power listed on their website.

[kend]

Does anybody know of a source for a +P striker spring?

We have them in stock.

[CMV]

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.

[z40acp]

This could be thread drift, but I just bought a 9mm pro. Noticed that the slide's breechface below where the firing pin hole is has a tear drop shaped indent in it. All {except the .45's} that I have seen have this in it. Could some brass shearing of the primer build up, especially when liberally lubed, and slow the firing pin down? Why did S&W put this in?

[Tokarev]

This could be thread drift, but I just bought a 9mm pro. Noticed that the slide's breechface below where the firing pin hole is has a tear drop shaped indent in it. All {except the .45's} that I have seen have this in it. Could some brass shearing of the primer build up, especially when liberally lubed, and slow the firing pin down? Why did S&W put this in?

I noticed my gun had a little carbon built up in this area. Scraping it out gently with a screwdriver made no difference in light strikes.

[z40acp]

Does your gun have an indent in it allowing the primer to flow back?

[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.