doublegunshop.com - home Forums General Discussion DIY Gunsmithing @ doublegunshop.com Broken bridle screw

I have a broken bridle screw that tumbled out of the lock mortise last night when I removed the lock after shooting in the rain. It is broken, and the remainder is still in the back-action lock plate. Looks like a size 4 or 5. I don't think it is a 6 but could be wrong.

I have yet to pull the bridle off and see what, if anything of the screw can be grabbed to turn. but assuming it broke below or at the surface of the lock plate. I am not sure how I'll get the screw out, but neat tricks for doing so are always welcome.

The lock maker is no longer in business, so I'm going to have to improvise. I cannot make screws from scratch. Assuming that I get it out and it is a generic size, what are good sources for replacements?

Should these screws be tempered?

Is it a savage backaction sidelock?

In this case, no. I am afraid it is not even a shotgun but rather a rifle, made by Carmen Axtell. But a back action lock is, more or less, a back action lock. I am hopeful that the screw is some standard size (.e.g., 5x40) but even if it is, I don't know where go get one. The Local Gun Shop won't have it, of that I'm pretty sure. I'm wondering if purveyors of muzzleloaders might have them.

The bigger problem is how to get the broken piece out. That I will work with tonight after doing chores. Kroil has been soaking it all day.

Measure one of the other screws in the bridle is the easy answer. If not work a wood dowel in the hole and see what you have. You most likely need a screw made for it, then case hardened. You could make one out of tool steel and then harden and temper but no need to on a bridle screw. It is not a big job but I doubt a store bought screw will be satisfactory.

I can easily pull one of the others for measuring. That's not a problem. Looks like Track of the Wolf sells various bridle screws so, with luck, one will fit and maybe they will be of good enough quality. I can get one made if I need to, but prefer not to call in those chips if possible. I was hoping there might be someone that specializes in these in a great variety of sizes (and of high quality).

Not knowing what the steel is in the TOW screws, case hardening might not be a good idea. not sure if they really need it, but some sort of tempering might be good.

I just spoke with Carmen, she suggested that you contact Shiloh and they should have the screw

Mike

Don't quit your day job Brent. If you don't like the screws from Track of the Wolf, run down to Home Depot and grab a box of these:

Yeah, I see it, but Carmen retired, sold her equipment and sailed off into the sunset some years ago.

I think if it were me, I'd figure out what size I needed, before I looked for a source or heat treatment guessing. Someone will know different, but I've never heard of hardened screws that needeed tempering prior to use.

If it's easy enough to measure one of the other screws, I'd try it in the hole that needs replacing just in case it's a different size. If it's a common size, then worry about quality. If it's rare, but a source turns up, why not just buy two or three? The possible sources mentioned so far would certainly know reasonable expectations for a gun screw.

If the screw sheared off anywhere near flush with the surface of the lock plate it shouldn't be any problem to remove the broken threaded end. I have done it many times with a tiny prick punch. You may need to regrind the tip of the punch to a needle-like point, according to how small a diameter the broken portion is. You may even need to make a tiny prick punch out of something as small as a large needle. All according to what you have on hand. Clamp the lockplate in a vise, horizontally, working with the inside of the lock plate facing you, if possible. Using the tiny prick punch and a tiny hammer, like a 2 oz., carefully try to start the screw to turning counter clockwise (assuming RH threads) by holding the point of the punch at 12 o'clock on the broken portion of the screw, leaning it to your right, and tap lightly with the hammer. It should start the broken portion to moving. If it's a bit stubborn go to the 6 o'clock position and lean the punch the other way. Alternate positions until the screw portion starts moving out. It will only get easier after it begins moving.

I have gotten many broken screws and bolts out of blind holes, or through holes, this way. If it fails, it's because the screw or bolt was torqued so much that it distorted badly in the threaded hole and is in a tight bind. But, this almost never is the case, IMO.

Good luck ....

SRH