Mis-fires with my M&P 9mm

[Hunter850]

Went to range today to check out my 9mm. 15-20 misfires from 100 rounds. Using MFS rounds ( according to the box made in russia) $12.95 box.
Most misfired rounds did fire on the 2nd attempt and 3 or 4 needed a third before firing. The majority occured during the first 50 rounds. Probably 5-6 on the 2nd box.
When I examined the casings the one that fired shows a different mark on the primer than the ones that did not fire. Both showed that the striker made contact but the fired casings also showed a slight mark in the shape of an V.
I had stripped cleaned and lightly oiled the pistol the day before.
Any thoughts or recommendations?

 

[marcham]

Quick google revealed dented but not fired primers somewhat common with this manufacturer in a variety of calibers.

 

[mlehtovaara]

Quick google revealed dented but not fired primers somewhat common with this manufacturer in a variety of calibers.

That many in 100 rounds is not common at all!

I have put several cases of that stuff through my Glock without an issue. The .223 performed like crap in my Rem R15 though, and was misfiring 2/20 but still nothing close to what the OP experienced.

Have you fired any other ammo? Really until you do all that is said here is gonna be speculation.

I highly doubt that that kind of failure rate can be blamed on the ammo alone though.

 

[Dsiwy]

Try some better ammo first

 

[Hunter850]

That is the only ammo available to me at the time. Hope to try some other to see if that is the problem.

 

[jackrabbit000]

It's the ammo, not the gun.

 

[IM_Lugger]

but the fired casings also showed a slight mark in the shape of an V

the V shape comes from the pressure of burning powder gasses pushing the primer back into the breech face/ firing pin channel.

The second one looks like a light strike. If your other 9's don't have a problem with that ammo, I'd be checking the firing pin channel for gunk/ excess oil.

 

[Shep546]

I shoot that crap through my M&P9mm all the time and have never had a single malfunction in well over 1,000 rounds... in fact I'm heading to the range tomorrow with some.

 

[mlehtovaara]

I shoot that crap through my M&P9mm all the time and have never had a single malfunction in well over 1,000 rounds... in fact I'm heading to the range tomorrow with some.

Like I said..........

15-20% failure?

There is something up with the gun!

I have never heard of such a failure rate with that stuff, or any ammo for that matter, and I am sure we would have since that stuff is popular as hell among many here.

 

[Hokus Grey]

Could be a gun problem, but you always eliminate ammo as the problem before you assess it as such. My thinking is a bad batch of ammo, given the type.

 

[TDC]

It's the ammo, not the gun.

Could be a gun problem, but you always eliminate ammo as the problem before you assess it as such. My thinking is a bad batch of ammo, given the type.

Most likely the comments above. Start with the cheap and easy fix, new USA manufactured ammo.

TDC

 

[xtremacanuck]

I didn't strip my M&P 40 until about 2000 rounds. Didn't have problem with firing pin protrusion at all.

 

[Hunter850]

I will certainly be trying the cheap and easyway first by trying another brand of ammo.

Anyone in the Halifax area now where to buy some 9mm.
I got these from Hnatiuk's, that is all they had in stock.

I removed the striker and cleaned out a lot of oil inside the assembly. Everything appears like it should nice and new and nothing amiss.

Thanks to youtube for complete disassembly video.

http://www.youtube.com/watch?v=KN6mbzypv0I&feature=results_video&playnext=1&list=PLE0292C639C7BF933

kevin

 

[xtremacanuck]

Your picture is pretty clear. I would say your firing pin strike is nice and deep. A light primer hit looks like a little dimple, not a full crater the diameter of the pin like your photo is showing.

 

[Clobbersauras]

My P2000 eats MFS like a champ. The M&P should run it fine as well.

 

[Wolfgang7]

Have you fired any other ammo? Really until you do all that is said here is gonna be speculation.

This!

 

[killer1963daddy]

my m&p 9 never missed a beat till i was shooting home rolled, the same ammo didnt miss fire in my chineese pistols, i guess the s&w is a little fussier than a np-20 or m-201

 

[00Buck]

I put many hundreds of MFS through a Ruger SR9 and only one light primer strike. We blamed the gun as it was fired so much it was burning hot to the touch.

 

[enefgee]

I removed the striker and cleaned out a lot of oil inside the assembly. Everything appears like it should nice and new and nothing amiss.

Thanks to youtube for complete disassembly video.

http://www.youtube.com/watch?v=KN6mbzypv0I&feature=results_video&playnext=1&list=PLE0292C639C7BF933

kevin

Yup, the striker channel needs to be dry - and the striker doesn't require oil, if it gets in there you can have light strikes. I use canned air to blow mine out when I've done a detail clean.

 

[mlehtovaara]

How cold was it?

My Maverick 88 only ever miss fired with light strikes when it was really cold, and I had over oiled the bolt/firing pin channel.

Possible if it was really cold, and the firing pin channel was full of oil it might have gummed up.

Were the misfires the first few shots after loading a couple mags? Putting your gun down for a couple minutes to reload mags, might have given the oil time to gum up, then once a few shots were fired it was enough to free the firing pin.

Just a thought.