View Full Version : Boring or reaming or drilling holes for tapping

11-23-2014, 12:00 PM
I find myself at a fork in the road that has way too many possible turns, and I'm looking for wisdom that only comes from experience(which I'm lacking ATM). I need to prepare a hole in my barrel(well two barrels actually) in order to be able to thread them to 7/8"-18. They are 12ga shotgun barrels so they are tapered, and I need to open them up and make the bore straight. My first attempt was to use a piloted counterbore to open them up, but the p.o.s. tool couldn't hack it so now I want to try something else. I was gonna buy a nice deming drill but a couple references specifically advised against using them to open up holes.
So I guess that leaves using a reamer, unless someone with more grey in their beard has some suggestions. Intended hole size is .821".

11-23-2014, 12:21 PM
Use a piloted reamer, won't work if there is any choke.

11-23-2014, 02:41 PM
It's is not clear to me what you are trying to do, but it kind of sounds like you want to remove choke constriction from the barrels. If so, you need to be very careful as it is an easy job to screw up. Suggest you contact mansonreamers.com or pacifictoolandgauge.com and discuss your job. They make tooling specifically for what you are trying to do ( I think).


11-23-2014, 03:10 PM
Yes they do. Those are the 2 best ones. There is also Clymer but I have had a lot of problems with their reamers in the past because not enough back clearance. You really have to wrestle with the Clymer to get it to cut, then the rubbing behind the cutting edge mars the finish. The other ones cut freely and leave a nice finish.

11-23-2014, 07:02 PM

RWO: no I'm working on rebarreling a shotgun turning it into a rifle.

Thanks for the help, I figured reaming would be the way to go but just wanted to make sure I was not mistaken.