When I was in 7th and 8th grade, I designed a large line of cartridges based on the 7.62x54R. Didn't have the money to build any at the time, and eventually lost interest (found girls, cars, etc.), then later when I got back into wildcatting I learned more about cartridge design and decided the x54 wasn't the best case for my intended purposes.
I don't believe the 41 was part of my plans; it's neat to see the case used for wildcatting! Good thing there's a rim for headspacing, as the shoulder is looking a little suspect for the job!