Hi all,

I damaged a taper pin hole on my FSB when I punched out the pin.  How do you clean up the taper pin hole without changing/removing the taper?  I was considering replacing the FSB, but it is my understanding that they come undrilled.

Next question....how do they drill a tapered hole?

All my best,
Rob

Quoted: Hi all, I damaged a taper pin hole on my FSB when I punched out the pin.  How do you clean up the taper pin hole without changing/removing the taper?  I was considering replacing the FSB, but it is my understanding that they come undrilled. Next question....how do they drill a tapered hole? All my best, Rob

Taper pin holes are reamed, not drilled.  You need a taper reamer, 2/0 size.  The FSB & barrel are set up in a jig and the holes are drilled undersized, then finish reamed to the proper size.  

Swapping FSBs is no exact science, as there is no standard as to where the pin holes are drilled and reamed.  There is very little chance of you getting a FSB with the same hole orientation as the one you have now.  Starting with an undrilled FSB is just about the same.  It is unlikely that you would be able to drill the holes exactly where they need to be to get the FSB exactly centered and uncanted.