Replacement Strain Screws

[Brewski]

Where might I find replacement strain screws for square butt S&Ws? I’m afraid I’ve gotten a little too grinder happy when tuning the mainspring. They don’t need to be stock – in fact I can’t find any. I’ve looked at using 8-32 machine screws from the hardware store, but I can’t seem to grind the heads down evenly so they fit into the countersunk hole in the grip. Thanks.

[6-shot]

Brownells. Link>>>> Click here

Scott

[inkedshooter]

You can try S&W. Had to call them once for the same screw and a couple smaller springs.

[earplug]

Chuck the hardware store screws in a electric drill and spin em while you grind them. If it looks wrong, it might be covered by your grips.

[chirpy]

Try prying the anvil out of a primer and sticking the primer under the screw for a quick fix until you get a new one.

Richard

[CJDOUBLETAP]

Brownells.

[Toolguy]

Use a 8-32 x 1/2 socket set screw from the hardware store. They are headless. Put it in with some blue Loctite and you can adjust it all you want and it will stay where you put it.

[Toolguy]

Use a 8-32 x 1/2 socket set screw from the hardware store. They are headless. Put it in with some blue Loctite and you can adjust it all you want and it will stay where you put it.

[Carmoney]

Put it in with some blue Loctite and you can adjust it all you want and it will stay where you put it.

Yep, it will stay put right up until it comes loose!!

Sorry, but I must respectfully disagree with Warren and the others who consider the strain screw an "adjustment screw." Particularly if you're shooting major power factor stuff, they can and do come loose! Several of you reading this post will recall times when your "loctited adjustment screws" came loose and caused clicks during major matches. (Don't worry, I don't plan to list names, but you know who you are!)

I believe that once the spring tensions are correctly adjusted, the strain screw should be loctited, tightened down good and hard, and left the fug alone.

[Tom E]

Use a 8-32 x 1/2 socket set screw from the hardware store.

I'm with Toolguy. 8-32 socket set screw, adjust to suit and Loctite. I use 290 (wicking) Loctite. The stock strain screws are junk, they're too soft and the tip deforms and gets a little shorter each time you turn it. Socket set screws are grade 8 fasteners. Much better stuff.

[Carmoney]

The stock strain screws are junk, they're too soft and the tip deforms and gets a little shorter each time you turn it.

This concern, spread largely via the little old hens on the S&W Forum, is grossly exaggerated.

If you're taking the strain screw in and out so often you wear out the screw, you might have an issue with OCD!

[Tom E]

This concern, spread largely via the little old hens on the S&W Forum, is grossly exaggerated.

It's a bigger deal if you run a stock strength mainspring. I worked on a 625-3 with a stock strain screw so mushroomed the tip was bigger than the thread dia. Had to be filed down before it could be removed.

Seems the only people who have problems with Loctite not holding are those that haven't learned to use it properly or use the wrong type or both.

[LPatterson]

This concern, spread largely via the little old hens on the S&W Forum, is grossly exaggerated.

It's a bigger deal if you run a stock strength mainspring. I worked on a 625-3 with a stock strain screw so mushroomed the tip was bigger than the thread dia. Had to be filed down before it could be removed.

Seems the only people who have problems with Loctite not holding are those that haven't learned to use it properly or use the wrong type or both.

Based on your absolute words of wisdom, perhaps you would care to share with those of us too dumb to know what we are doing. If Loctite has made it, I have probably used it. BFD, I received a strain screw from S&W via Brownells that was so long it would have probably done what you saw on that 625-3.

MR. MURPHY loves people like you.

[jhgtyre]

This thread is not about how to fasten the screw. Lets keep it about finding a screw and the options that are available. Beat on one another via PM if you must.

-Larry Drake

The Moderating Team

[usmc1974]

? I’m afraid I’ve gotten a little too grinder happy

Been there, more then once.

[Brewski]

I really am im pressed with the wealth of knowledge on this forum - thanks for everyone's input. I finally found some 8-32 x 1/2 set screws that Toolguy recommended at Home Depot, stainless no less. Our local hardware store - which had a huge selection of fasteners - went under when a Lowes opened in town. The set screws work perfectly. Carmoney's concern about the screw unscrewing under recoil over time seems worth keeping in mind. I plan to find the sweet spot for the strain screw and Loctite it in place with the blue stuff (why does it come in a red bottle?. I'm going to scribe a mark on the frame and the set screw so I can keep an eye out for any movement. This is on a model 67 shooting ammo at a PF of about 130 for IDPA and ICORE, so we'll see what happens over time. In a worse case senario, I'll get a click instead of a boom - which at my skill level is about the same difference .

[jjanglin]

If ya dip your screw in some acetone blow it off dip again let it dry then lock

tite it, the loctite will set more even and not tend to come loose.

Acetone is about the same as Loctite brand primer.Carb cleaner and brake clean

do a good job put leave a bit of a residue not visable to the naked eye.

Remember to use this stuff in a well ventilated area.Will make ya

if ya dont.

Jim/Pa

Sailors

[Brewski]

If ya dip your screw in some acetone blow it off dip again let it dry then lock

tite it, the loctite will set more even and not tend to come loose.

Acetone is about the same as Loctite brand primer.Carb cleaner and brake clean

do a good job put leave a bit of a residue not visable to the naked eye.

Remember to use this stuff in a well ventilated area.Will make ya

if ya dont.

Jim/Pa

Sailors

Excellent - will do.

[Tom E]

I plan to find the sweet spot for the strain screw and Loctite it in place with the blue stuff (why does it come in a red bottle?.

Blue (242) Loctite is fine but if you use Green (290) you can just put a drop on the exposed screw threads after you get it adjusted and it wicks into the threads. No need to remove the screw, apply loctite, and re-install.

[CRDB]

Brewski,

I have a new strain screw you can have.

Dean

[Craigar45]

Try prying the anvil out of a primer and sticking the primer under the screw for a quick fix until you get a new one.

Richard

This is the hot tip... I would only add that you should use a *spent* primer.

C

[David Sinko]

What's the best way to REMOVE one that has been secured with Loc-tite? I was going to disassemble and inspect my old 617 and didn't realize that when I had the action job done it was reassembled with Loc-tite. I buggered up the stock strain screw when the screwdriver slipped. I should still be able to unscrew it if I can break the Loc-tite on the first attempt. I have heard that heat is the way to go. What's the best way to do this?

Dave Sinko

[COF]

Heat - not enough to damage the metal but enough to break the loc-tite bond. A propane torch should have more than enough heat for that.

[Tom E]

Acetone will dissolve Loctite. Takes a while to wick in and soften and weaken the Loctite.

[Brewski]

I plan to find the sweet spot for the strain screw and Loctite it in place with the blue stuff (why does it come in a red bottle?.

Blue (242) Loctite is fine but if you use Green (290) you can just put a drop on the exposed screw threads after you get it adjusted and it wicks into the threads. No need to remove the screw, apply loctite, and re-install.

Now that sounds like a very good idea. Instead of having to find the right tention point and then count turns as I back the screw out and then put it back, I could simply find the right tention and apply the 290, let it cure and be done.