Thread: How to make a D-type reamer to chamber a barrel

A removable pilot is not really required unless you are going to be chambering multiple barrels with variable bore sizes. For a one off job, just sizing the pilot to the barrel on hand is fine. I tend to make a seperate plug before making the reamer, so that I can figure out exactly what pilot size I need, then I dont have to test fit the barrel while trying to make the reamer as I know what size to hit. You could do a removable pilot by just making the pilot section longer with a step down, then you can drill and tap the end of the reamer for a retaining screw, then make the bushing.

I make my pilots quite long and cut the flat section onto the pilot so that I have a place to measure half thickness. I do the same at the other end with a parallel section and cut onto that a ways. I then make a note of those diameters before I start cutting it in half so that I can tell exactly how far I need to go. This will also allow you to see if you are cutting the flat section with a taper and be able to correct it.

I still cant upload photos. Iv played with the settings and poked around, but the photos simply wont upload. Anyone know why this is happening?