Buggered screw hole on receiver...need help please

[alnitak]

Well, per my earlier thread, I'm building a pre-64 puzzle gun, Just about have all of the parts, including matching lever, link, locking bolt and breech bolt (thanks for the recommendation!).

Here's my problem. I'm starting to assemble the parts and realize that the Finger Lever Pin Stop Screw hole is buggered up! The screw almost falls through completely. I can get it to engage what is left of the bottom of the threads, but if I tighten, the bolt won't move. When I loosen sufficiently to allow the breech bolt to move freely, the screw is very loose and I suspect will back out (or fall out) easily.

So, is there anything I can do to repair this (short of re-threading the hole for a larger screw, then tooling a screw to fit the same dimensions inside the receiver)? Maybe leave the screw loose and put nail polish, Elmer's Glue or something temporary to fill the gap and harden, but allowing for later removal as needed? Blue Loctite, and live with the small gap? Is there some metal filler (like Loctite Form-a-Thread) that can be used on a more permanent basis?

Thanks.

[7.62 Precision]

There are a number of things that could be done, and others will likely chime in with better ideas:

How are the threads and the head of the screw? The head and threads should stop it from going too deep. If it goes deeper than it should, and has threads that it can engage, you may want to just screw it in deeper and cut it flush inside the receiver. If the screw is at all beat up though, replacing it with a new one might help a bit.

You might try locktite; again, it depends on how much engagement you are getting with the existing threads.

There are epoxy materials that can be tapped. I have seen it done, but I don't care for the idea, especially with such small threads, but people do it.

The hole can be welded and re-drilled and tapped, this should be OK since it is pre-64, but increases the work that has to be done.

The hole can be opened up and re-tapped for a larger screw. You would just have to have someone make the screw for you, should be pretty easy and not too expensive.

The hole can be opened and a helicoil added http://www.stanleyengineeredfastening.c ... ad-inserts You would have to make sure they make one with the correct threads and depth, or cut to depth.

[Mescalero]

Heli-coil

[Blaine]

Heli-coil

+1

[Chuck 100 yd]

Rotsa ruck finding a heli-coil THAT size.

What I would do is buy a new screw if the one you have has any damage at all and a trick lots of gunsmiths do is..... Place a piece of (about 6lb.) monofiliment fishing line in the hole with the end hanging out and screw the screw right in along side the fish line. The fish line will make the screw quite snug in the hole and prevent it from coming out on it`s own accord. Makes a great thread locker and is totally non damaging and removable.

[alnitak]

What I would do is buy a new screw if the one you have has any damage at all and a trick lots of gunsmiths do is..... Place a piece of (about 6lb.) monofilament fishing line in the hole with the end hanging out and screw the screw right in along side the fish line. The fish line will make the screw quite snug in the hole and prevent it from coming out on it`s own accord. Makes a great thread locker and is totally non damaging and removable.

That sounds like a solution worth trying.

I do have a new screw, so it's not the screw. Looks like the screwdriver head was too big and the previous owner just gouged out the metal around the screw. Consequently, the head of the screw doesn't stop against the receiver, but I suspect is stopped by the threads as I screw it in further.

For the fishing line, do you have to be careful that none extends into the receiver so as not to interfere with the breech bolt movement? Once I screw in with the line in place, is there anything (clear, temporary) that could fill the gap around and under the screw head...maybe creating a "bedding" for the head?

[Chuck 100 yd]

If it does stick through inside, just open the lever/bolt and trim it off flush with the inner wall.
Possibly a very thin washer under the screw head would do the trick also. At the hardware store,look at drywall mollies. They have a hardened paper thin washer under the screw head that may be just the ticket. Good luck,Chuck

[alnitak]

How are the threads and the head of the screw? The head and threads should stop it from going too deep. If it goes deeper than it should, and has threads that it can engage, you may want to just screw it in deeper and cut it flush inside the receiver. If the screw is at all beat up though, replacing it with a new one might help a bit.

7.62...the screw is new. Since it's the Lever Pin Stop Screw, is that something I can cut flush with the receiver, or does the non-thread part of the screw need to extend in further to keep the lever pin from backing out?

[alnitak]

If it does stick through inside, just open the lever/bolt and trim it off flush with the inner wall.
Possibly a very thin washer under the screw head would do the trick also. At the hardware store,look at drywall mollies. They have a hardened paper thin washer under the screw head that may be just the ticket. Good luck,Chuck

Thanks Chuck.

[Mescalero]

Aircraft supply house will have almost ANY size.
You would not want to see th AN commercial books that contain these things.

[flatnose]

http://www.mcmaster.com/#helicoils/=qif2ur

[765x53]

Wouldn't a helicoil require drilling out the original threads or am I mistaken?

[Nate Kiowa Jones]

OK,
Here's a trick I have to use quite often with the very same screw but on the current Rossi 92's. Rossi is notorious for D&T-ing the hole too deep. What I do is make a lock washer for it using about 3/4's of a single coil from a coil spring that is fit the screw and is thin enough to go into the hole too.
You may have to try different size coil springs until you fin one that is just right. hope this helps

[flatnose]

765x53,
It would require drilling out, although it seems that may not be the problem.
If there is enough thread left, but the screw is going in too far, a washer under the head will do, or bed it with JB Weld or MarineTex. JB is cheaper, and will actually hold a screw thread. Give the screw a few coats of car wax, then start it into the threads. Use a matchstick and work some JB under the head of the screw. Screw it in to the required depth, and wipe off the excess. Loosen the screw 1/2 a turn after 5 or 6 hrs, and let the JB set up hard for 24 hrs, that is using the regular JB, and not the Quick.

[flatnose]

Nate's idea sounds pretty good. Try ACE hardware for the spring.

[Mike Hunter]

Since you provided no pictures, nor exact measurements, here are a couple of thoughts:

I’m a strong believer in keeping it simple.

The rife is a pre-64, which means that that particular screw has not been made by the Winchester factory in 50 years, so very likely it’s not NOS, and was made aftermarket.

Did they make the screw correctly? +/- .005 will make a difference.

The only job for that screw is to keep the link pin from falling out, so it’s a very low stress screw.
What I would do is remove the bolt, screw he screw all the way in and dress it down level with the inside of the receiver; about a 5 min job. If you are concerned about it staying, place a single drop of med strength Loctite upon final assembly.
No welding, no helicoils etc.

Mike

[alnitak]

Thanks all for the good suggestions. I will probably do some combination of the fishing line, JB Weld and/or the spring coil for a lock washer. Sounds like they will do the trick without significant effort.

Now I have to go find a hammer replacement. Found out last night (after installing the mainspring) that I have no half-cock safety. Looks like 3/4 of the trigger nock has been sheared off...another part to get!

[Pete44ru]

.

I would alternatively suggest using a small bit of plumber's thread-sealing Teflon tape (about $1 @ HomeCheapo/Lowe's) to flesh out the threads, since there's no stress/pressure on the lever pin stop screw.




.

[AJMD429]

Now I have to go find a hammer replacement. Found out last night (after installing the mainspring) that I have no half-cock safety. Looks like 3/4 of the trigger nock has been sheared off...another part to get!

If that is the case, you have to assume there was some major stress put on that piece, and the SEAR would have to be the part doing that, so it could easily have some hairline cracks or damage. I'd replace the 'sear', too. In the case of the Rossi 92, if I'm not mistaken, the 'sear' is part of the trigger.

[alnitak]

Good thought, Doc. Thanks.