M*CARBO Brotherhood

I striped the hex screw. What now?

I need to uninstall the single point of attachment “ring” on my SUB-2000. I used Blue Locktite on the threads during installation - per the instructions. Now, I want to do a major installation of the interior parts.

I obviously don’t know much about gunsmithing, but is there a secret to backing-out the screw that I have bunged-up the hole (hex key)? It is a pretty small screw.

Am I doomed, or do I need to locate a gunsmith shop?

Any help appreciated.


Try sticking a rubber band over the head of the screw and then put the Allen key into the head through the rubber band. Sometimes that works.


Like this


Could you take a picture of the damaged screw and give me an idea on size? What size Allen key?

I know a few tricks.


I know a few tricks as well what manufacturer of the single point ring? clamp type that goes around the castle nut? Ive drilled em out, ez outed em out, used a hot allen key and a hand impact to take em out, cut a slot with a drimmal and even used a screw driver to take em out. all depends on your application. pic would be great


I’ve had good luck with screw extractors in the past, but that screw might be a wee bit small. here’s one from home depot. Sometimes though you need to drill out more material so it can bite.



I think I will need a little heat to deal with the blue LockTite. Have heatgun, will shoot.

Several good ideas — I’ll ask for more help if these fail me.

Thanks for the help, brothers.


careful with the heat around the plastic. thats why i usually heat up a spare hex wrench by sticking it in the hole, and heating the wrench. let the heat transfer to the screw…


You can also use a soldering iron to heat just the screw.

If you can get your hands on left handed drill bits, that’s the fastest and easiest way to remove small screws.

A small center punch to tap it out (unscrew) will typically work but it’s slow.

I haven’t had much luck with screw extractors. The big easy outs work great but the smaller ones leave a lot to be desired.


Good tip!
Thanks for the ideas.


@archibaldal If it’s a Phillips Head Screw Find a Some Valve lapping compond and put in the head of Screw with a good new bit,Or if it’s the Allen head 6 point! Tap in a Twelve point style Allen and it will act like a Easy Out.


Beat me to it. And, yes, use heat to break the Locktite bond.


Okay, I’m ready to try this – and thanks for all the tips.

In preparation (and thanks to all your advice), I purchased enough stuff to try everything – even things I had never heard of:

Screw extractor set
left-handed drill bit set
soldering iron - electronics
valve lapping compound

Starting with most conservative since I believe that my failure to apply heat for LockTite was my initial mistake – place the stock in the armorer’s vise then try heat, lapping compound, and original hex key.

I’m obviously hoping that I won’t need to escalate.

Following Disassembly, I will be polishing the MCARBO internal upgrades, then re-assembling. I don’t feel super-confident (being a super novice), however, Chris’ videos seem to show everything I need to know.

I’ll update this hex key project post - wish me luck.



Luck be with ya, but you got this brother, aint no big thang.


I felt the same way when I did the trigger kit about a month ago. I was about 50% sure that I was going to end up having to take a box of parts to my gunsmith, but everything came together without too much trouble. And now I have a sub 4# trigger on the sub 2000! If you follow the video and take your time you’ll be fine! Good luck!


OKAY – Success!

I think the big secret was using the soldering iron to apply heat to loosen the LockTite. Also, I was using the Valve Lapping Compound with the hex key that MCARBO supplied with the part. As I inserted the hex key I could feel the grit of the lapping compound – I’m imagining that it helps increase the “bite” of the hex key against the shoulders of the well of the screw. I was also careful to ensure that the hex key was fully inserted down into the hole. I applied the soldering iron to the middle of the screw – about a minute before I tried a serious twist.

Next project - remove the tube and hone it with stones and honing solution. Then do the internal parts - every part MCARBO presently has available.

Time to watch the videos - again.


@archibaldal :+1::+1: You’ll Remember that little Trick in your bag of Trick’s :grin:


glad it worked out for you!


Yep. Thanks for this tip — never even heard of lapping compound before.

Even though it is a small tube, I have enough left to remove 100,000 more.


@archibaldal Your Welcome! Find ‘‘Snap On Tool Dealer’’ Or on Line, Look for their replacement bits for the Magnetic Screw drivers and buy a couple of the # 6
With the Serrated Edges ! Once you use One you will never let them out of your Sight! They are Magnetic and don’t wear Out under Normal use, I used 2 bit’s for 1500 Square feet of sheet rock on my place.