Have you thought about using the Auto Zone Pulley Puller to press out your barrels? $20 and about 20 min. grinding a couple small reliefs into the jaws so that they fit the trunion better. I have pressed out a bunch a barrels with it using only a 1/2" drive ratchet and a few pennies. I do put the jaws in my vise to ensure that they don't pop off during the press. But other than that It's almost too easy.
Here's a couple pics;