If it is not running true, you will cut an out of round chamber. Chuck the drill in the tail stock chuck, as you
will have to drill out the chamber end about 1.250. This will remove enough metal so the finish reamer
won't have to cut much.
Now set a small lathe dog on the reamer, and with a center in the tail stock, move the tail stock up close
enough to the barrel so the reamer will be in the barrel next to the shoulder of the reamer. Have the
reamer in the tail stock center. Leave the lathe in back gear setting that you used for threading and with
the tail stock fastened down. Slowly feed the reamer into the barrel, keeping plenty of cutting oil on the
reamer.
You can rest the lathe dog on the compound, while feeding in. Be sure that the reamer is on the tail
stock center when you feed it in as if it isn't it can grab and break the reamer. ALWAYS HOLD THE
REAMER BACK AGAINST THE TAIL STOCK CENTER. Usually at first you will be able to feed in for
a depth of about 1/8 inch, before removing the reamer and blowing out the chips. As you get down to
the shoulder area, the feed in is less.