It certainly appears that in the old days shooters didn't agonize over this chamber length business like we do today. The SAAMI meeting where it was "suggested" that manufacturers start marking the chamber length on their guns was in 1937. Savage seems to have begun during 1938, as I have one gun that letters as 1938 that has this --

The Wildfowl I had just had the top line --

and then had CHAMBERS spelled out on the barrel flat --

For some reason the Wildfowls I've examined have CHAMBERS spelled out on the barrel flat --

while the Super-Fox guns just have 3 IN.