Headspace gauge

[65joe]

I have a Predator action that has a pinned Holland recoil lug and two barrels threaded for this action,switch barrel). I'm about to switch the barrels for the first time, can I just spin one barrel off and the other one on, or do I need a headspace gauge when I switch the barrels? I have a Davidson vise and action wrench. How tight do I tighten the barrel to the action?
Thanks

 

[tightneck]

Assuming the job was done by a reputable smith, then the headspacing should be dead on for both barrels. If you have any questions about that, then you will need two HS gages. The bolt should close easily on the Go gage, but not close on the No Go gage. Changing barrels is a snap with a pinned lug. Clamp the barrel in the vise, insert wrench and twist the action off. Simply use the reverse to install the new barrel. Whenever taking an action off or tightening onto the barrel, do not bring the action up tight with a jerk. I like my barrels pretty tight, and use a steady torque to seat the barrel shoulder to the action face.

 

[RJinTexas]

Joe, I always check the headspace with a gauge, there's no such thing as being too safe. I had my smith put a witness mark on the bottom of all my barrels to assist it getting the headspacing dead on and I still remove the firing pin assembly to get a positive feel and check with a gauge. If you don't want to purchase both gauges you can just apply a piece of tape to the face of a go gage and use it for a no go gauge. I use 3M's blue painter tape as it's close to .004 thick which works out well and is easily removed without leaving gum on the head of the gauge, I no longer purchase no-go gauges. All my switch barrel actions have pinned lugs.

RJ