Gunsmithing Stuck scope base screw

[longrange772]

Well, I was about to mount a new scope so removed old scope and was going to put a fresh set of scope base screws in. During the removal process, one of the torx screws promptly decapitated by my bit. It does have blue loctite applied but that has never been an issue before. Actually, as I was attempting to remove, it didn't feel like I was applying much pressure. I assume not the highest quality steel for the bit. Don't think I have ever had a bit give before stripping the screw. Anyway, tried a magnet to get it out, needles and a hot glue gun with no success. Part of me thinks, well that bastard is in there tight, just leave it and replace the others. I wasn't planning on changing the rail but still don't like that it is in a non-optimal state. The screw is #8-40 and most of the screw extractor sets I have looked at don't seem like they are meant for something that small. I have read some other threads where the recommend just using a drill bit to remove enough of the head to get the rail off and then use pliers or something to get remaining piece out. Of course, drilling into the top of my action ...

Just wondering if someone in the community has been in a similar spot and has a novel solution.

 

[Threadcutter308]

Well, I was about to mount a new scope so removed old scope and was going to put a fresh set of scope base screws in. During the removal process, one of the torx screws promptly decapitated by my bit. It does have blue loctite applied but that has never been an issue before. Actually, as I was attempting to remove, it didn't feel like I was applying much pressure. I assume not the highest quality steel for the bit. Don't think I have ever had a bit give before stripping the screw. Anyway, tried a magnet to get it out, needles and a hot glue gun with no success. Part of me thinks, well that bastard is in there tight, just leave it and replace the others. I wasn't planning on changing the rail but still don't like that it is in a non-optimal state. The screw is #8-40 and most of the screw extractor sets I have looked at don't seem like they are meant for something that small. I have read some other threads where the recommend just using a drill bit to remove enough of the head to get the rail off and then use pliers or something to get remaining piece out. Of course, drilling into the top of my action ...

Just wondering if someone in the community has been in a similar spot and has a novel solution.

A really good way to get heat into the screw is with a soldering iron with a small dab of solder on the tip. Hold the tip of the iron/dab of solder on the screw head for about 10 seconds. But, heat all by itself probably isn't going to help you much. In that case, follow mcameron's advice.

 

[msgriff]

Probably too soon to need these, but Engineer's screw extraction pliers work great for stripped heads.

 

[WeiserBucks]

Well, I was about to mount a new scope so removed old scope and was going to put a fresh set of scope base screws in.

What made you decide to change the screws?

 

[Trigger Monkey]

Agreed, it seems a little unwarranted to swap out scope base screws for "fresh" ones when the installed ones haven't given any issues up to that point.

That being said, I ran into an issue about a year ago with a small 4-40 screw on an ambi-safety and ended up drilling the head off so the lever could be removed and then slotted what was left so I could remove it with a flat head screw driver. I posted about it here and there's some other good info in the thread that may help you.

Stripped Screw in Ambi-Safety

Last night I tackled an issue that had been bugging me for a while. I had a lower receiver that had a CMMG ambi-safety on it that was hitting my trigger finger when I swiped it and it no longer needed it anyway. The problem is that the screw head holding the right side lever on was stripped...

www.snipershide.com

 

[Bantam1]

With a Torx there are times where you may be able to pound the next size larger Torx bit into it. Use some heat to heat the screw and the threadlock should return to a liquid state and spin it out.

 

[longrange772]

With respect to fresh screws, I had a couple that were shaking loose, obviously not the one related to this post, which were gunked up with some old loctite. FIgured I would replace them and try vibra-tite VC3 since I was swapping out scope and rings (too low for larger objective lens scope).

I tried left handed bit and screw extractor without luck. Thought I better cut my losses before doing real damage. Found a local gunsmith who was able to remove it. Had to remove material almost down the the receiver before the rail came off. Wasn't enough material left on the screw to grab with pliers so he drilled into the screw left in the receiver and was able to get enough bite on it to push through the receiver. Took about an hour of work. Everything cleared out and no damage to receiver.

Always thought I was pretty conservative in my application of loctite. Looking at this video, they are slathering it on compared to how I apply it.


Only thing I can think of, is maybe loctite re-applications over time made it build up and get really tight or that, as mentioned in the video, it acted as a lubricant and I ended up over torquing though my reading was true to installation spec.

Think maybe I will just tighten more often than deal with this again.

 

[hlee]

I haven’t had a torx bit fail, but I have had a couple that looked like they wanted to. I have one that looks like a casting of the rifling of a tiny barrel. My bet is that your bit just failed, but if it had not, the screw would have come out normally. It was just that the remnants of the bit in the screw prevented anything but extra-ordinary measures to remove the screw.

Looks like I finally rounded it off on the last use…

 

[hero's machine]

Typically you'll need to go the opposite direction of how it broke off. The engagement will need to reach a neutral state and then they should relax and about fall out.

Drilling a potentially hardened piece of steel is going to make a mess unless you have carbide endmills.

I'd start by working upside down and attempting to release the bite on the bit with a little prick punch.....don't swell the head or swedge it in.....just tap it lightly.

If that fails, carbide or grind the head down just a bit and try again. If that fails, take the head off. Heat is your friend on locktite....400* will make all the difference.

 

[Eagle1899]

^^^^^^^
This. Get a sharp punch or a pick and get the broken off bit out. It will take a bit of finesse to get it out. It's locked in there from twisting torque. Then after you get it out, use a soldering iron to heat the screw up before you try again.

 

[redneckbmxer24]

It’s hard to tell by your pic if the piece of the bit is just locked up in one direction a little or if it’s completely twisted and mangled in there.

If it’s just locked up you can use a narrow chisel and smack it with a hammer and that will most likely loosen the piece of bit up. Just make sure you don’t get into the screw material at all because you’ll stake it together and it will never come out.

You could also just put the other screws back in or the new ones and torque them down and pretend that issue doesn’t exist until you actually need to get the base off instead of just wanting to replace the screws for some reason.

 

[longrange772]

It was locked in there with twisting torque. We tried a few things to get it out with no luck. Gunsmith eventually got it off but my lesson learned is if this were to occur again, like @redneckbmxer24 said, put the other screws back in and pretend the problem doesn't exist.

 

[Easy_E]

Another way to remove that screw is to sacrifice the scope base , cut the base beside the screw pry up and the base will snap in two . Grab the head with some small visegrips and twist. We run into this with Savage rifles when we remove the two piece bases the screw heads are soft and strip easily .