In a pinch you can use a long extension for a 3/8 drive socket set. The end of the reamer will fit in the drive socket of the extension , and you can drive the extension by clamping the 3/8 square end in a large tap wrench. The reamer will have to be pulled from the chamber with something like a long-reach needle nose pliers, cleaned, and replaced with the same pliers before re-engaging with the socket. This method is not very convenient, but it works fine. When you ream a chamber by hand, the rifle should be held in a vise with the barrel down and the action straight up. This helps to prevent "ovaling" the chamber. Use a lot of Rapid Tap or a similar cutting fluid to lubricate the chamber and the reamer. Just clean it off and oil when you are finished or your reamer will rust.
Clemson