If I remember correctly, back in the 60s or 70s there was a cartridge called the .44 Automag. A .30-06 case was cut down to standard .44mag length to be used in an auto pistol, (the wildey maybe). As far as full length I think the .411 Hawk is the largest that has been done successfully. Any larger and you lose any useable shoulder to headspace on. But I could be wrong.
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