I have the drill piloted and extended its cutting at .3125 a little on the small side so I extended a 8MM reamer its finishing at .3148, the liner foes in with just a light drag. Slides in easily and stays in place. Drill and reamer are both long enough to frill from one end and leave the original muzzle crown if i decide to ( just open it up to .245-.250 dia).
I am going to bore a sleeve to match the barrel taper to hold it securely.
Am planning on using anchor lube to drill and ream with. Its a very good high pressure cutting lube and is soap water clean up.
Right now the plan is 1/4 turn on tail stock 1 full turn then clear chips. On my lathe 1/4 turn if the hand wheel is .031. I may make a tail stock stop so I can slide the tail stock to clear chips easier. Also planning on a empty tool holder on the compound set to support the drill and reamer so I dont have to deal with the sag.
Im getting closer to putting Dads Model 61 Win into service