Does anyone know if you can use the Lee Breech Lock Press in the single stage mode? Will it accept a bushing that converts it to single stage?

You just leave the bushing locked in the press and screw the dies in and out of the bushing to use it as a standard single stage press.

Thanks for the reply, do you konw if the bushing can be replaced by a Redding bushing, the type that is removed for 50 BMG dies. My thinking is the tolerance would be tighter with a standard thread-in bushing.

The Lee breech lock bushing OD thread is not standard to any other press/bushing. I doubt replacing the bushing with a fully threaded one would change much, since the press's threads are interrupted too.

Lee makes a 50 BMG adapter for its Classic Cast press. It is not the same as the breech lock, which is a quick-change system of half threads, and not simply a size adapter. I don't own one, so I've never measured the breech lock thread form to see what it is, but in the photos online it appears to be a finer thread pitch than either the big .50 dies or an adapter for their female thread in a die frame has?