m-4, I am "told" it is a 43 Mauser. There is a 10 day grace/examination period. I've been shooting a 43 Mauser in a double for about 20 years now so I have brass and molds with which to compare and am "fairly familiar" with a few of the variations in bore diameter and case dimensions. Fortunately for me the double is pretty much the standarized military 43 Mauser cartridge. The cases and molds I bought worked fine. There's a quantity of Cerrosafe just waiting to be used to make another chamber cast. I agree with you, absolutely and completely, that a goodly portion of the pleasure of owning vintage firearms is in the bringing them back to life. I do hope the rifle barrel of this cape gun works with my current batch of loaded cartridges, then it will just be a matter of finding a load that will work. If not, then you and I share boat space....lol.