I started assembling the barrels onto the receivers today, it takes about an hour per gun.
first the barrels are turned, then pressed into the receiver. the receiver holes were reamed and honed to get them straight and round before hand.
the barrels are pressed in with a head space gage till they stop, then the flaps need to be checked to make sure both are making contact, which they usually do not so the longer flap needs to be trimmed.
When both are making contact the next step is to drill and ream the cross pin hole.