M629-1 rear sight leaf screw hole stripped

[papercutninja]

I'm the 3rd (at least) owner of my M629-1. The previous owner didn't shoot it at all and did not have anything done to the pistol. I have shot just under 20 rounds out of it. There has been trigger work done, with a very light single-action trigger pull as a result. I found a problem today, which is very major. At some point, the screw-hole for the rear sight as stripped out. Unbeknownst to me, the sight was then glued on. Yesterday, i took it out of the safe to inspect and clean it, and upon cocking the hammer back, the rear sight fell off.

What are my options at this point to have this repaired? I'm not necessarily looking for a home remedy; i'm fully aware that this is going to need professional repair.

Note the glue residue on the underside of the rear sight leaf.


a view of the screw-hole, looks elongated to the left.


The hole itself has no thread left, except at the deepest part of the hole. Not enough for the screw to lock into when the leaf is attached.

 

[Arisin Wind]

I wonder if you could use JB Weld or one of the thread repair epoxies.

 

[MichiganScott]

A competent gunsmith should be able to drill and tap it for the next larger size screw. A Helicoil insert would work if they make them small enough.

 

[Engineer1911]

Helicoil kits

Emhart Teknologies, Shelton, CT • Tel. (203) 924-4737​

Link: http://www.noblefix.com/PDF/Helicoil/HeliCoil-Professional-Kit.pdf ​

See page 4 for the chart below. Helicoil kits are made but I don't know where to buy the tiny sizes.​

Thread Kit Insert, Ea. Installation Removal
Size Part No. Length R E P L A C E M E N T I N S E R T S Tap Tool Drill* Tool Size
INCH COARSE Short 1 Dia. Medium 1-1/2 Dia. Long 2 Dia.​

4-

40 5401-04 12 1185-04CN112 1185-04CN168 1185-04CN224 04CPB 2288-04 #31 5/64

5-40 5401-05 12 1185-05CN125 1185-05CN188 1185-05CN250 05CPB 7551-05 #29 3/32
6-32 5401-06 12 1185-06CN138 1185-06CN207 1185-06CN276 06CPB 2288-06 #25 3/32
8-32 5401-2 12 1185-2CN164 1185-2CN246 1185-2CN328 2CPB 2288-2 11/64 1/8
10-24 5401-3 12 1185-3CN190 1185-3CN285 1185-3CN380 3CPB 2288-3 13/64 1/8
12-24 5401-1 12 1185-1CN216 1185-1CN328 1185-1CN432 1CPB 2288-1 15/64 5/32
1/4-20 5401-4 12 1185-4CN250 1185-4CN375 1185-4CN500 4CPB 2288-4 17/64 3/16
5/16-18 5401-5 12 1185-5CN312 1185-5CN469 1185-5CN625 5CPB 2288-5 21/64 7/32
3/8-16 5401-6 6 1185-6CN375 1185-6CN562 1185-6CN750 6CPB 2288-6 25/64 9/32
7/16-14 5401-7 6 1185-7CN438 1185-7CN656 1185-7CN875 7CPB 2288-7 29/64 11/32​

1/2-13 5401-8 6 1185-8CN500 1185-8CN750 1185-8CN1000 8CPB 2288-8 17/32 25/64

​

 

[dlbx2]

I had a similar experience with a 4 inch 29-3. My local gunsmith did exactly what was suggested in a previous post. He just found the next bigger size tap, ground the screw to be exactly flush with the frame above the forcing cone, soaked it in blueing, and if you didn't know that it had happened, it would look like it came that way.
DLB

 

[retired_diver]

I would have it drilled and tapped for the hole that is there ie. might not be the next size up due to the elongated hole. I am the original owner of a 629-1 and it had the best single action trigger I still have ever shot (out of the box). My trigger scale indicates a break at exactly 3lbs. So yours might or might not be worked on. My screw has loosened up many times and has been tighten. I put locktite blue on it so it can be removed and it has held up great. My 629 has well over 9000 rounds thru it in 37 years of shooting it. It's a little loose now though. Still love this gun.

 

[Mike McLellan]

Explore the possibility of using a post '92 sight assembly. The screw is bigger (6-48 I think), and you might be able to make a clean repair without a lot of work. Take a deep breath and get lots of opinions before you make up your mind. Good luck!

 

[tomcatt51]

Explore the possibility of using a post '92 sight assembly. The screw is bigger (6-48 I think), and you might be able to make a clean repair without a lot of work.

Yes and no. The "later" front sight hole is in a different place and goes with the 3 hole pattern in the top strap. The holes are 6-48. The "new" front sight hole will (usually) just clear the "old" front sight hole. You would only need to drill and tap the front hole but while you're at it why not all 3?

Most original looking fix would be to tap the stripped hole 6-48 and use a later sight screw. Would require a slightly larger countersink in the sight.

I not sure if you can get a heli-coil for the oem thread.

 

[papercutninja]

Thanks for the suggestions, guys. I'll investigate the heli-coil situation to see if there are ones small enough, but i think ultimately i'm going to find a good gunsmith to do the work.

 

[TAROMAN]

A gunsmith who's a competent and properly equipped (vertical mill) machinist can make short work of this with a properly sized heli-coil as 1911engineer has located.
Many so-called "gunsmiths" aren't machinists at all and would likely just make things worse.

 

[tomcatt51]

A gunsmith who's a competent and properly equipped (vertical mill) machinist can make short work of this with a properly sized heli-coil as 1911engineer has located.

He "located" common size heli-coils, which this may not be and probably isn't. The size of the sight screw on the later guns is 6-48. See that in the list he "located"?