If you have a good drill press you can use the hand reamer in it. You will need a drill press vice that has a verticle grove cut in it or a V-block like in the pics here on his mill table. Then you will have to make sure you table on your drill press is level-square. You can check that with a rode with a bend in it chucked up in the drill press with a dial indicator. Then ream the chambers but just turn the chuck by hand not with the power on. Use a little cutting oil,tap oil or kerosene on the reamer. It will turn pretty easy because it wont be removing much metal anyway. Set the stop on your drill press shallow at first and reset until it reams just in as far as you will ever seat a ball. If you are turning the chuck by hand it would be very hard to mess anything up like that
Yes, that's the Brownell reamer I was talking about And yes, I would have to buy the pilot set. If it works OK on the 1860 Army, then I have a couple Remy's and a Walker that might get their cylinders reamed. Your test results show significant improvement in accuracy