Sometimes German Chambers are cut tighter. I owned a16ga German Gun marked at building with 70mm chambers, yet I discovered that they were cut tighter than my Belgian marked 70mm chambers. So much so brass RMC hulls fire formed to the Belgian gun through repeated use could barely slip half way into the German gun. Yet the German gun was clearly marked 70mm.

It maybe the gun built for earlier fiber wads is more narrowly chambered and it is likely 65mm or if marked 70mm.

Michael Dittamo
Topeka, KS