Greetings All,
The .303 case is actually shorter than the 405 and will become even shorter when expanded. The .30-40 Krag case is a little longer, if you can find any, but still comes up short. As far as the rim goes either of the the above cases will fit with about 0.2 mm excess head space. One of my .303 rifles has more than this but functions well with low pressure loads. If you decide to use .303 cases select those with the thickest rim and longest case. Some cases I have have rims down to 1.4 mm and short case lengths as well. The best option would be to buy the right case in the first place. If you are building a rifle you can get the chamber cut to suit your cases. From memory some recently built 405 rifles will not chamber original cases with their thicker rim.
Regards Grandpamac.
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