Am following this thread with some interest. I used to have an 1899 sporter in SOME version of the 6mm round, It was in the 75000 range as well. I have Gene's book. My rifle was marked ".236", but it was my understanding that such rifles were "supposed" to be stamped "6mm". I wonder if it might have been chambered for the fat-cased ".236 Remington", a rare rimmed cartridge (thus not the Navy round, or at least not the more common version of it) which was chambered in a few rolling blocks. Anyone have any ideas? Thanks in advance.