Tuning Stripped Bolt on my M3

[kaylaindy]

I removed the Arca 2 rail/trigger guard off this gun to get to the rear reg adjuster. One of the 4 screws stripped out when I went to tighten it.

The screw looks like it lost some thread on the very end. I'm hoping the screw went and the threaded hole on my M3 is intact.

Do you think this will be the case? ...like are M3's always harder than screws? 

It's one of the front screws that holds the trigger guard on. 3 screws definatley won't hold the rail.

 

[cahil_2]

Probably steel screw and the receiver is aluminum, so probably receiver is stripped. Might be able to go with a slightly longer screw or retap it if that is the case. 

 

[Metalmaniac]

The machine bolts are most likely a high carbon steel alloy for strength because of such small diameter bolt with sharp grooves cut in it. ( threads ) . Sharp edges cause stress risers. Places where it can or will break

The receiver is an aluminum alloy.

When assembling any part especially aluminum parts. You need to start the bolts with light pressure turning backward till you feel and hear a click . This aligns the starting point of the threads. Then start turning the bolt in the proper direction. Never tighten the bolt all the way down until all the bolts are started. That can cause mis alignment. Then run all the bolts down lightly then torque them down evenly in a cross pattern. Never force any part. If you are unsure back the bolt out and try the bolt in the hole without the part on the assembly. All this information is a little late but I hope it helps in the future. MM

 

[kaylaindy]

When assembling any part especially aluminum parts. You need to start the bolts with light pressure turning backward till you feel and hear a click . This aligns the starting point of the threads. Then start turning the bolt in the proper direction. Never tighten the bolt all the way down until all the bolts are started. That can cause mis alignment. Then run all the bolts down lightly then torque them down evenly in a cross pattern. Never force any part. If you are unsure back the bolt out and try the bolt in the hole without the part on the assembly.

I got slighlty longer screws with some tiny lock washers to fill any space. I will use that info for sure form now on. Thanks! -Nate 

 

[Glem.Chally]

Basically all the screws go into aluminum threads, be gentle. That's probably the reason there's so many screws so they each only have to do a bit of work.

 

[kaylaindy]

FX made the hole deeper than Saber Tactical made the bolt. When I put a 1-2mm longer bolt in, it tightened all the way. 

Hoooraayyyyy! I have never been so relieved in my life. Good call guys! Thank you!

and thanks to Ace Hardware!

 

[oldman70]

thanks for this write up i did same thing same screw it didn't take anything to happen. I'm always very careful about that. so everyone beware. 

 

[marl3y]

In my rifle those front screws are shorter. There are grub screws buried in there to prevent a leak path. Shorter screw, fewer threads engaged, so greater likelihood of stripping. Heard newer versions are machined differently, not requiring the grub screws, and therefore maybe the front trigger guard screws are as long as the ones in the rear.

 

[Healthservices]

Those of us who have been working on these things for so long should have torque drivers to keep us from doing mistakes like this. Yet I know the majority of us don't.

 

[darkskyy]

Those of us who have been working on these things for so long should have torque drivers to keep us from doing mistakes like this. Yet I know the majority of us don't.

Are the torque specs listed somewhere or what is the general rule?

 

[Bigragu]

Anti seize is my friend on all pcp fasteners anymore, So all of them get that treatment.

 

[kaylaindy]

Anti seize

Is that lock tight? It sounds like the opposite. 

---

I would have dabbed some lock tight on ...but my trigger guard will be coming off 100+ times in the next year. I have to do videos on all calibers and slugs liners in each caliber. 

I hope this doesn't become a problem. 

What is the tool to get to your rear reg adjustment without taking the guard off? Anyone done it or have a picture of the tool?