Broken a Drill Bit Off in an Aluminium Lower

**RKillcrazy** · March 6th, 2021, 07:14 PM

I was working on a lower I had laying around and I was just about done with the job when I broke off a 5/32" drill bit in one of the holes for the pins. Any idea how to get it out? Best I can come up with is drill in from the other side and attempt to knock it out with a punch.

**ROCK-IT3** · March 6th, 2021, 07:26 PM

That's what I was thinking. Use a drill smaller than 5/32", in case you are not in the exact location, then you can continue to drill from the original side and remove the smaller hole. You'll probably break the smaller bit when it hits the tip of the other one, though.

**Xringshooter** · March 6th, 2021, 08:09 PM

Is any of the broken drill accessible from the inside of the lower? If so, you might be able to grab it with needle nose vise grips and turn it back and forth while pulling it the rest of the way through. If you have not milled out the fcg area then you really don't have any choice except coming through the other side and trying to punch it out.

**Walleye Hunter** · March 6th, 2021, 08:17 PM

If there's a piece sticking out from the entrance side, you could grab it with pliers, vise grips and spin it backwards. It should let go pretty quickly and easily. If you're done gouging out the body , a pair of needle nose may grab it inside the cavity and spin it backwards.

**RKillcrazy** · March 6th, 2021, 08:51 PM

Tried backing out the bit with pliers but, no joy. The pocket has been milled. The bit looks to have broken as soon as it began to break through and into the pocket. So, there's - maybe - 1/16" sticking out on the inside of the pocket. The bit looks to have shattered and anything I could grab from the outside has broken off to look much like what is seen on the inside.

**RockIsland** · March 6th, 2021, 09:29 PM

Maybe try to drilling out the corresponding pin hole on the other side of the receiver. Then try hitting it out with a thin punch from that side.

**RKillcrazy** · March 6th, 2021, 09:33 PM

Originally Posted by RockIsland

Maybe try to drilling out the corresponding pin hole on the other side of the receiver. Then try hitting it out with a thin punch from that side.

Yeah, that was my initial plan. Once I get another bit, I'll be trying to pop it out from the other side.

**Walleye Hunter** · March 6th, 2021, 09:40 PM

It is logical that it would break when breaking through, that is when they grab and shit happens. Go easy and use oil to help prevent that.

**Hoppy** · March 6th, 2021, 09:48 PM

Originally Posted by RKillcrazy

Yeah, that was my initial plan. Once I get another bit, I'll be trying to pop it out from the other side.

I think you end up enlarging the other side hole when the new bit hits the broken one and doesn’t stay centered. Vice grips if you can grab a hold of anything

**icp4life162005** · March 6th, 2021, 09:54 PM

Originally Posted by RKillcrazy

Tried backing out the bit with pliers but, no joy. The pocket has been milled. The bit looks to have broken as soon as it began to break through and into the pocket. So, there's - maybe - 1/16" sticking out on the inside of the pocket. The bit looks to have shattered and anything I could grab from the outside has broken off to look much like what is seen on the inside.

Drill the other side proper, and use a punch to punch it out from the new hole.