S&W fails me

[Mulie87]

Bought a new M&P 10mm. Mounted a Holosun red dot and took it out to sight in. After about 50rnds  I feel something hit my hat, I look down and see my sight missing. The S&W supplied screws sheered off and the sight flew off behind me. I am beyond disappointed and mad. I’ll be calling S&W on Monday for warranty wirk.

[boneaddict]

That would be disappointing!    I hope the rest of the firearm is sound.

[callturner]

Let us know how that works that's what I carry. Did you torque the screws to the factory specs or possibly over torque them?

[Mulie87]

Let us know how that works that's what I carry. Did you torque the screws to the factory specs or possibly over torque them?

I did not see any published torque specs in the owners manual. I was careful mot to tighten them too much, but I guess it’s always a possibility.

[wadu1]

Pleas post your reply from S&W. Had the same thing happen on a 1911 with an aftermarket red dot.

[b23]

Let us know how that works that's what I carry. Did you torque the screws to the factory specs or possibly over torque them?

I did not see any published torque specs in the owners manual. I was careful mot to tighten them too much, but I guess it’s always a possibility.

Having been guilty of strong arming more little screws/bolts than I care to admit some years ago I bought a inch lbs torque wrench, in fact I now have two of them one being a Wheeler Fat Wrench.  Once I started using the Fat Wrench to torque things I quickly learned why I had been breaking so many of those little POS's I'd been cussing.  The problem all along had been the dumbazz with the wrench in his hand, aka Me!  Until you use a in/lb torque wrench to tighten things that only take 10-15 in/lbs you don't realize just how little that tiny amount of torque really is.  In fact, that's actually why I have two in/lb torque wrenches because I didn't believe the first one I bought was reading correctly, it just seemed so little, and I bought a different one to confirm the first one was right.  My mom always said I was a slower learner. 

Just looking at those, it looks like you likely over tightened them and it looks like you put red or some kind of loctite on the threads which when wet can almost act like a thread lubricant which makes it that much easier to over tighten and twist the heads off.

The really bad news and hopefully this isn't the case but if that is red loctite you may have to have those milled out.  I hope not but it's a possibility you may want to prepare yourself for.  Regardless of the what and why, it's a really sucky situation and I feel for you.  If you don't already have one get yourself an inch pound torque wrench like the Wheeler Fat Wrench and start using it all the time on those tiny little screws and bolts.

[Mulie87]

Pleas post your reply from S&W. Had the same thing happen on a 1911 with an aftermarket red dot.

Will do. Filed my warranty claim already.

[Mulie87]

Let us know how that works that's what I carry. Did you torque the screws to the factory specs or possibly over torque them?

I did not see any published torque specs in the owners manual. I was careful mot to tighten them too much, but I guess it’s always a possibility.

Having been guilty of strong arming more little screws/bolts than I care to admit some years ago I bought a inch lbs torque wrench, in fact I now have two of them one being a Wheeler Fat Wrench.  Once I started using the Fat Wrench to torque things I quickly learned why I had been breaking so many of those little POS's I'd been cussing.  The problem all along had been the dumbazz with the wrench in his hand, aka Me!  Until you use a in/lb torque wrench to tighten things that only take 10-15 in/lbs you don't realize just how little that tiny amount of torque really is.  In fact, that's actually why I have two in/lb torque wrenches because I didn't believe the first one I bought was reading correctly, it just seemed so little, and I bought a different one to confirm the first one was right.  My mom always said I was a slower learner. 

Just looking at those, it looks like you likely over tightened them and it looks like you put red or some kind of loctite on the threads which when wet can almost act like a thread lubricant which makes it that much easier to over tighten and twist the heads off.

The really bad news and hopefully this isn't the case but if that is red loctite you may have to have those milled out.  I hope not but it's a possibility you may want to prepare yourself for.  Regardless of the what and why, it's a really sucky situation and I feel for you.  If you don't already have one get yourself an inch pound torque wrench like the Wheeler Fat Wrench and start using it all the time on those tiny little screws and bolts.

Thanks, b23. That does look like lock tight and was included in the box from S&W. So any repairs still on them. I do have a torque wrench but didn’t think of using it🤦🏻‍♂️

[Mulie87]

I went ahead and ordered an aftermarket steel plate and screws from C&H Precision at the advice from a friend.

[follow maggie]

What b23 points out is a super common mistake. I’ve made it more times than I care to admit. The fat wrench is definitely one of the better tools I’ve bought.

[jaymark6655]

Yep, the ends of what is left looks like they were over tightened. Not hard to do on those tiny screws. I wouldn't be surprised if torque is only 5 in-lbs, not cool that it wasn't listed in the manual. Looking it up online, #6-32 is around 6 to 10 in-lbs. depending on material.

[Rat44]

Had the same issue with a 1st generation of the mountain gun.
 Kept shearing off the rear sight screws.
The screws were actually too small for the recoil of a light weight 44 mag.
Just an issue of poor engineering at the time.
Went back to the factory 3 times,traded that one off.

[Mulie87]

I heard back from S&W. They sent me a return label to ship it back for warranty repairs. I’ll be sending it back tomorrow.

[okie john]

+1 on using a torque wrench. "Farmer tight" is too much in a lot of cases.


Okie John

[Mulie87]

Update: I got my pistol back from Smith & Wesson a couple days ago. I reinstalled the optic using a metal base plate and different screws. I took everyone’s advice and use a torque wrench. Instructions on the site said 15 inch pound. When I install the screws, the angle is not perfectly vertical. There’s a slight angle which caused the inability for my torque wrench to reach the 15 inch pounds. The wrench contacted the optic as I neared max inch pounds. This caused the screw bit to skip and start to strip the screw. So to finish it off I just gave it a little love tap with a stand alone Allen wrench. I have not shot it yet, but crossing my fingers, it does not break again.