Obviously the WRA drawing wasn't too hard to come up with.............
HH ... Tis True, it's been around since
January 1918!WRC, I suspect, increased their case rim diameter from 056-057 to 057-062 because the toggle links on the original rifles were getting sloppy, generating misfires
But the story goes like this: Chaparral did their pre production re-engineering of the 45-75 Winchesters based on Jamison/TenX brass that TenX 'proposed' to make.
Hobie, I believe, is the only person that has announced that they have received any of the 45-75 TenX loaded ammo, with cases made by Bertram - 4198 powder and Magnus bullets. Talk about sub-contracting!
Then in some time in mid-stream of production, with the excess head space issue and brass with a 057 rim thickness that generated misfires, they changed to the 1918 WRC cartridge blueprint dimensions (057 to 062). It's my understanding, though I have not touched one of new cartridges that are being made in Germany, ... it's a clone of the this blueprint with a 062 rim thickness - which is OK with me. Resized 348's are 062 but with a smaller rim diameter and the 348 shoulders reduces the head space to ZERO! With 400 rounds through the barrel - not one misfire
Would have been 450 rounds, but our 100-200-300yd match got rained out today
For what it's worth, just after we received our rifles, 3 of us did a 100yd test shoot using 20grs of 4198 and 23grs of 5744 reloads with the Lee 457-340F bullets. The XMP5744 groups were winners - hands down