Drilling holes without burrs

Topical Discussions include anything pertaining to Gunsmithing.

Moderators: JackF, Harold_V

Post Reply
Posts: 169
Joined: Tue Oct 20, 2009 9:39 pm
Location: Durban South Africa

Drilling holes without burrs

Post by atunguyd » Thu May 12, 2022 2:53 pm

Hi wondering if anyone can make any suggestions here?

A shooting mate has asked me it is is possible to drill porting holes into a pistol barrel, of course this is a pretty straightforward operation, just drill into the barrel which is normally not hardened at all. Problem is how would one go about doing this without ending up with burrs in the bore and rifling?
Obviously trying to remove the burr inside a rifled barrel is not something easily done.

Russ Hanscom
Posts: 1906
Joined: Wed Mar 15, 2006 11:10 pm
Location: Farmington, NM

Re: Drilling holes without burrs

Post by Russ Hanscom » Thu May 12, 2022 5:51 pm

Two options come to mind. One, make a plug that fits into the area, then drilling into it will not leave room for a burr to form. Second, I have seen neat little counter sinks for doing the inner end of the hole. No idea of where you would find one - I think I saw them at Boeing surplus many years ago.

User avatar
Bill Shields
Posts: 7750
Joined: Fri Dec 21, 2007 4:57 am
Location: Somewhere in the World

Re: Drilling holes without burrs

Post by Bill Shields » Thu May 12, 2022 7:38 pm

Or EDM drill them...

ID back chamfering is a trick when boring in to a cylinder.

It is straightforward to do with a small lollypop cutter and a CNC mill. Tough to do otherwise.

Shiva makes tools for this but if you hit one of the rifeling grooves, then you have a burr that will be trouble.

I would bite the bullet and pay someone the $ to EDM drill it.
Too many things going on to bother listing them.

Post Reply