Stupid Shield 9..

Old Unk

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Purch 11/15
Shot it 11/16

going back to S&W ASAP- defect/flaw in bolt face, a chip adjacent to firing pin hole..allows primers to flow. Next step probably a pierced primer.

While I know S&W will make right, it is irritating to have waited for so many months just to get a firearm that never should have made it out of quality control.

Arrrrrgggh!

NOTE 11/19/12 - issue resolved- see my last post..
 
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Can't tell you however flowing primers from two(2) different factory loads on all rounds fired is not within specs.

What would be the purpose of relief cut on any bolt face near any firing pin hole IF it allowed primers to flow.

It almost looks like a TEAR at the bottom edge of the firing pin hole in the shape of an inverted triangle.

My good camera is headed to HI with my daughter and cellphone pix marginal so nothing to post.

Best.
 
A couple definitions from the SAAMI glossary

PRIMER CRATERING
A circumferential rearward flow of metal surrounding the indentation of a firing-pin in a fired primer cup.

PRIMER FLOW-BACK
See Primer Cratering.

PRIMER LEAK
The escape of gas between the primer cup and head of the cartridge case, or shotshell head.

PRIMER SETBACK
The condition when a primer, or battery cup primer assembly, moves partially out of its proper location in the primer pocket of a metallic cartridge or shotshell during firing.
 
Jyezahn, better than I could do- thanks. Normal firing pin strike
on the primer leaves a FLAT surface with centered FP indentation.

My primers are raised/flowed and an indistinct FP strike.

No expert however raised primers usually a sign of excess pressure
not the case here. Have fired both loads extensively in my 6906, Glock 26 and no primer issues.

The chip on the bolt face near the FP hole is a flaw/defect

I'll advise on what S&W finds and does

Best
 
I agree with you, call S&W and demand a new slide. They machine the slides out of a solid bar of stainless steel. Through the machining process someone could have nicked it. Or the stainless bar could have had a tiny air bubble that caused an imperfection and those that should have inspected it, missed the flaw.

Either way it does not matter. Get it fixed to your satisfaction.

Bob
 
From my understanding that Tear shaped relief in the breechface is normal. All M&P handguns have it. It is a little updside down triangle at the 6oclock position under the firing pin hole. Your problem may be caused by out of spec parts. You need to get the gun looked at. S&W is great and they are quick on returns but be professional with them. If you get irate you ruin you chances of getting this resolved in a timely manner.
 
Jyezahn, better than I could do- thanks. Normal firing pin strike
on the primer leaves a FLAT surface with centered FP indentation.

My primers are raised/flowed and an indistinct FP strike.

No expert however raised primers usually a sign of excess pressure
not the case here. Have fired both loads extensively in my 6906, Glock 26 and no primer issues.

The chip on the bolt face near the FP hole is a flaw/defect

I'll advise on what S&W finds and does

Best

I have the same indentation below the firing pin hole on my M&P 9c and M&P 40 FS. My sigma 40 doesn't have one. I collect and reload all my brass and I've never seen anything that looks like a primer problem?

P.S. Here's a shot of the 9c firing pin hole with the indentation right below it. The focus is not real good, but the indentation shows up. I don't think that is a mfg flaw since it's present in both M&Ps.
 

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Factory loads in proven performers -Remington and WW.

stev32k, most, if a not all, of my firearms firing pin hole are concentric- round. If I'm looking at your picture correctly it looks like you have a dished out area at 6 o'clock on the edge of the FP hole. Might look at fired round primers, just for grins.

Appreciate the caveats on being civil - not a hater but was not a happy warrior yesterday.

Best.
 
Like I said I collect and reload all my brass and I've never seen anything that looked like a primer problem. I have 150 fired 9mm cases in front of me now and all the primers look normal. Just a nice round indentation on each.

P.S. Maybe some other M&P owners could look at their firing pin holes and see if any indentation is present. Guess I could have two defective guns and not know it.
 
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From my understanding that Tear shaped relief in the breechface is normal. All M&P handguns have it. It is a little updside down triangle at the 6oclock position under the firing pin hole.

It is normal and supposed to be there.

It's purpose is to alleviate primer shear and firing pin breakage. (common issue in striker fired guns.)
looks weird to someone use to the standard round firing pin indent from a hammer designed gun, but it's perfectly normal.

The hotter the load you shoot, the more you notice it. (if you look)
My USPSA production minor loads (approx. 26K p.s.i.) show no primer flow, however, Gold Dot +P or Cor-Bon +P (35K-37K p.s.i.) show significant primer flow. If you were to step up to USPSA major 9 loads (42K-45K p.s.i.) and you have to switch to a small rifle primer to eliminate pierced primers…just like you would in a 1911.
(I'm not advocating major 9 loads in any stock M&P, just using it as an example, as people are now building open guns on the M&P platform.)

Hope this helps.

Jeff
 
A pic of the bolt face and spent primers would be helpful. Mine has the same relief at the 6 o'clock position on the bolt face on my shield 9 also. I worried about a tear shaped primer strike on my spent primers till I started looking at all the spent pistol primers at my gun range and 99% looked just like mine so I worry no more. Normal IMHO but it won't hurt to contact S&W CS.
 
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Same here.. It's there.. A nice smooth elongated dish at six o'clock. My understanding is that it's suppose to be there as well.. My fired primers look fine, however I can see a faint image of the dish on the primer.. I vote normal.. Ron
 
Mine has the same triangular cutout on the face. All primers I've ever looked at looked normal. Never have shot a +P or reload in the 9c though.
 
photo-118.jpg


This is my .40 shield. (Shield 9 is with my wife at work) FS.40 is the same. Same relief cut in the breech face. No idea what its for but i have thousands of rounds through my fs40 duty gun with zero malfunctions.
 
Interesting. OK so many of you have the tear shaped place at 6 o'clock on the FP hole of your M&P's and have experienced no problems with primer flow or irregular FP indentation on the primer.

I went and looked at my striker-fired Glocks who use a rectangle shaped FP. Does the 9 Shield use a ROUND firing pin nose? Have never looked at a Glock FP primer strike but on my to do list.

When the defect OR FP hole relief cut was first mentioned here I thought maybe it was just tool chatter on the bolt face when starting to drill the hole.

Maybe I'm just getting old but am sure used to round FP primer indentations and no primer flow.

I'll talk with S&W early next week.

Appreciate the comments.

Best.
 
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I have four M&Ps; two full size and two compacts, one each FS and Compact in 9mm and .40 (with .357 Sig barrels for the .40s). All have the relief cut. Marking of the cut occurs on primers fired in all four pistols. As far as I'm concerned that is a normal condition.

I remember the first time I saw a 9mm case fired from a Glock in the late 80s. I picked some cases up at a range and wondered *** made a rectangular firing pin mark...
 
Have the tear shaped cutout at 6 o'clock on the FP hole of my early production Shield 9mm. I collect and examine all my brass - Nothing unusual with any of my brass...
 
Old Unk

Your OP was that you had a defect in the bolt face on your Shield 9. So I thought it was a defect in manufactruring from S&W. Now after reading the other posts, I examined my Shield 40's slide. If what you are referring as a defect, is a slight undercut at the bottom of the opening for the striker hole, then it is not a defect, but an engineered relief machined into the bolt face. My Shield 40 has the "V" shaped relief cut into the bolt face. It is about 1/32 inch long, and 1/64 inch deep at the circumference. It tapers into the circumference of the striker hole.

Bob
 
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All of my primers smear into the relief cut on the slide regardless of bullet weight and whether or not they are +P. This is on three separate M&P 9mm pistols.

It's all normal Unk. Call them on Monday and they will have you send in a pefectly good pistol and keep it for three weeks before returning it to you with a note saying that it is within spec.
 
Take a look at the spent round they sent you with your new gun from the factory. I just took a look at the one they sent with my Shield 9mm and it looks like what you are describing.

IMG_4896.JPG
 
I figured it out Unc!! I looked at several of my 7-8 M&P's... all have the same machined out spot at 6pm... Sooo, I think you should contact Glock and all the other manufacturers about the defects in their slides!!! :D:D:D
 

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