WOW! That is beautiful looking with no barrel nut? Please explain how the barrel is fitted and who did the work. What is the process to change barrels? Is it still as easy as a standard Savage? Must have details. Very cool.
It's fitted just like any action, has a shoulder instead of a nut.
Barrel change is actually easier but you need an action wrench and a barrel vise. It's easier because the headspace is the same with no need to adjust it like you have to with the nut.
The only drawback is you cannot have someone make a barrel without them having the action or knowing some critical dimensions for your particular action.