Mickey,
many continental guns are mounted very tight. This is on purpose: it will take a little while (perhaps a hundred rounds or even more)for the gun to 'break in', but it will stay tight for a great many more shots thereafter. Notice the position of the locking lever on a typical belgian double: it stands somewhat off center to the right.This is a 'reserve' for wear, a way to compensate automaticaly for the wear to the locking surfaces. Also, the barrels are not in touch with the watertable of the action,there is a small reserve for them to sink lower, so it takes a lot more shots for the barrels to come 'off face'. My younger brother was a student under Marcel Thys, who often had to explain the tightness of his guns to American customers.
Greetings,
Livinus