broken .062 drill bit removal?

[deerstalkert]

drilling the vent in a .32 barrel tonight and the tip hooked the edge of a land. snapped below the surface of the flat. unbreeched it and the tip of the bit just shows. not enough to press out from inside.
any good ideas for removing it?

this should be better than a stuck ball thread!

 

[2 shots]

can you tap it through from the outside ?? with a proper size punch

 

[deerstalkert]

tried a little but didn't want to enlarge the hole any. i may try some kind of fulcrum gizmo from the inside i thought about while eating. do my best thinking while eating or sleeping!
if only it had gone a few thousands deeper ! at least the breech plug came out without a fight. now i can put anti seize on it before reassembly.

 

[Kevin]

It's probably not stuck very bad, just the tip hung up on the edge of the land, try raddling the barrel on the breach end with a plastic headed hammer, or if you can get the bit to turn just a fraction to the left it should fall right out.

 

[deerstalkert]

been there , done that and the thing is Stuck! may try freezing it to see if it will loosen from the metal difference between the barrel and the drill.
thanks for the suggestion though, I really didn't smack it like it was a politician though, i will go try it now i ate!

 

[Tumbledown]

Bend a nail at a 90* angle and use the point to push the bit out from the inside. If you bend it to the right length at the elbow, you might be able to wedge it against the far side of the barrel like a crowbar.

 

[Colonial Boy]

If you use a soft punch smaller than the drill it should drive through without enlarging the hole.
However hit gently or the punch might get stuck as well.
Have had success with brass punches in similar (but different) circumstances.
Luck.

 

[EC121]

Punch it on through and install a liner.

 

[deerstalkert]

what i thought was the tip of the drill bit inside the barrel was some fumunda. got the bore scope and looked closer ,the bit didn't penetrate.
of course the vent i was drilling is dead center of where i need to drill for a liner. this is going to be a challenge.
thanks to all for the ideas and keep them coming.
this has to be as entertaining as a stuck ball thread.
maybe drill another small hole close to the broken bit, get it out of the picture and then bore for a vent liner with an end mill? that would help keep the bit from walking with the two holes already in there?
what do you think?

 

[Caniborrowsomeammo]

Maybe try a left hand 1.5mm bit in a pin vice? 1.5mm is a wee bit smaller than .062 I believe.

 

[Kevin]

Worse comes to worse, have it burned out by somebody local that has a laser engraver. Broke the second left hand bit trying to back the first one out. I have a lot of experience fixing mistakes I have made over the years. Hate to drill a hole.

 

[Rich44]

Before starting to drill another mistake/hole lets touch base on drilling small holes in steel. You should be no less than in a drill press and with the piece locked in place. Using proper speed for this size drill should be at least 3,000 rpm and the most important trick is drill to the stop. Meaning adjust your stop to a just touch, raise drill, turn stop a good .010 and drill. Get in the rhythm and just keep repeating, takes no time at all. You did not do this and when it was just ready to break thru the drill jump forward and hooked in. You well not get yourself in this trouble if you follow the above.

Since the drill is not thru enough to push back with a dentist tool. Then you probably need to heat end of drill with propane torch and attempt to drill with same size drill. You only need to heat .020 -.030 of the drill quickly and repeat as many times as it takes to drll the length. If you can get in a milling machine use a carbide ball end mill they work great with no heat necessary. But remember use the stop or you will just break another one. If you are going to go bigger to a liner size than just get a carbide ball end mill and just drill it out like it was not even there. Try to use a carbide ball end mill.

 

[deerstalkert]

Rich44, from your lips to Gods ear!. at this juncture your suggestion is about the only way. using a carbide ball end mill. no way to heat the end of the bit as it is below the surface of the flat. i have a buddy in town so i guess it's down off the mountain and to town again. twice to town in a month! gives me the heebee jeebees!
thanks everybody.

 

[Rich44]

While a carbide ball end mill is your best friend now. 1/16 dia. mills have mostly 1/8 inch shanks, and the depth of cut is limited. If you would tell me how much depth of cut is needed I can see if a 1/16 carbide ball mill can be held in the spin index on the surface grinder with a diamond wheel to turn down a relief area to give that needed depth of cut. And if possible, would put in envelope and mail to you. If your friend is a tool man he may provide you with a idea seeing it in person. Good luck

 

[2 shots]

SHOOT IT OUT --- just kidding- you read that alot on here with all kinds of stuff stuck in barrels.. truly, good luck with it. milling sounds the best. could you use a larger end mill and install a 1/4 or 5/16 liner depending on barrel size ??

 

[ZUG]

I would get a small tipped tweezers and try to wiggle the drill bit loose. It broke off because it got jammed on the cutting lips not the shank of the flutes. The tip is the only part that is stuck and if you can free it then you might be able to twist it counter-clockwise and remove it - worth a try

 

[deerstalkert]

tweezers that small don't exist here in the pucker brush i live in, but good idea.
Rich44, the barrel is .8125 across the flats.
bore is .308
subtracted and divided x2 equals .2522 if my math is correct!
i am going to try to order some diamond hole saws with one being .125 inch.
if that is the od cutting dimension it should just surround the bit and leave me a pilot hole for the 13/64th i need for a vent liner tap.
will probably be 6 months after i die that the stuff is delivered the way deliveries are going!

 

[Whitworth]

Well I might as jump in. If you have punch that small (or can make one) I would try to tap it on thru. If you broke thru to the bore there can't be too much metal left. If that fails then go with the end mill. YMMV

 

[Nameless Hunter]

Are you near a medium/major city with manufacturing? You might try looking for a fabrication shop with a laser cutting system. You'd be amazed at how many thousands of laser cutting/drilling systems are scattered all over the country. A careful alignment and a few quick pops with a 3+ kilowatt laser will precisely vaporize the drill bit without damaging anything else. I bet most fabrication shop owners are hunters themselves and will get kick out of helping you out. It's a non typical way to solve your problem but lasers have been used to drill very precise holes for decades now. Quick and clean.

 

[Rich44]

You do not need to order. Can send 1/8 inch carbide ball end mill Tue that will allow for that length. And will still check on 1/16 carbide length and get back to you. No charge.