Help with a 4mm stripped hex head screw!!

[M5NSX]

Gentlemen,
I have a 4mm hex screw I can get out of the forward rail on my Ritter & Stark bolt gun. Tried all of my tricks. Anything I’m missing? Any good gunsmiths near Clinton Township that could help? Don’t want to mare the finish. Thanks!! Dan

[Ol` Joe]

https://www.aimsindustrial.com.au/su...-with-4.0mm-dr

[joepistol]

A young friend was changing the oil in his 1st m/c..and managed to twist the head off the oil drain bolt, on the bottom of the engine case.
As I knew my gunsmith was a machinist, before he became a gunsmith, (what better training ? ! ) I asked him the best way to remove the threaded portion
of the bolt, that was still in the case. He loaned me a "reverse twist" drill bit..& it removed the piece like magic. As the bit is drilled into the bolt,
being a reverse twist, as it started drilling into the steel, the reverse twist force backed out the remaining piece of metal.

Couldn't believe how well it worked. I'd look for a reverse twist drill, small enough to fit the head of your bolt, & give it a go..

[M5NSX]

Thanks for the replies guys.

[Mohl]

Could try tapping a torx bit in and try backing it out.

[denniscoon@aol.c]

Any chance that loctite was applied to the threads? If yes, try using an electric soldering gun and heat up the screw, the heat will melt the loctite and the screw should come out with no problem, unless the head of the screw is messed up.

[M5NSX]

Tried the torx bit unfortunately it didn’t work. No loctite on threads and did try the electric soldering iron still a no go. Probably have to try an extractor and hopefully that gets it out without ruining the finish or threads.

[Norton]

You could try dry ice & heat cycle, use gloves.
Then try the torx trick.

[RifleGuy]

A young friend was changing the oil in his 1st m/c..and managed to twist the head off the oil drain bolt, on the bottom of the engine case.
As I knew my gunsmith was a machinist, before he became a gunsmith, (what better training ? ! ) I asked him the best way to remove the threaded portion
of the bolt, that was still in the case. He loaned me a "reverse twist" drill bit..& it removed the piece like magic. As the bit is drilled into the bolt,
being a reverse twist, as it started drilling into the steel, the reverse twist force backed out the remaining piece of metal.

Couldn't believe how well it worked. I'd look for a reverse twist drill, small enough to fit the head of your bolt, & give it a go..

THIS is how I have removed a lot of broken bolts over the last 30 year. Soak it with a bit of Kroil (or acetone & transmission fluid), apply some heat, then very carefully start a small diameter reverse drill in the center.

If you have a drill press or mill, you can use that to apply some enthusiastic down force on an extractor.

[RifleGuy]

Tried the torx bit unfortunately it didn’t work. No loctite on threads and did try the electric soldering iron still a no go. Probably have to try an extractor and hopefully that gets it out without ruining the finish or threads.

Though not desirable, damaged threads can be repaired several ways; TimeSert (or similar), over-drill and tap to a larger diameter, or overdrill, insert a threaded steel 'plug' that has been center drilled and tapped to the correct thread. (I've done this to repaired cylinder heads where an inexperienced technician botched the drilling of broken exhaust studs in a one-of-a-kind cylinder head. Kind of a homemade helicoil/timesert) It's like plugging a hole in wood with a piece of dowel rod. (Rifle stock repair where a sling swivel has been torn/stripped out)