Ideal and Lyman imprinting can be a bit hard to read--esp. as our arms shorten with aging. #257283, not #257-83. Alrighty then.
RCBS makes (or made) a similar design in their line of 'Cowboy' moulds, the 25-85-CM. I have one of these, and it does good work in my 25/20 WCF, but is velocity-limited to black powder performance. Up to about 1300 FPS it runs very well, but between 1300 and 1400 FPS it goes galley-west and prints about Improved Cylinder at 50 yards. 7.0 grains of IMR-4198/Rem #6-1/2 primers has been its best load, it will hold about 1.25" at 50 yards from my Marlin 1894CL and aperture sights. Bump the coal up to 7.5 or 8.0 grains (following Ross Seyfried's black powder cartridge equivalency formula) and the slugs 'Go Shotgun'. Gas checked Lymans #257420 and #257312 stay accurate well past 1700 FPS in this same rifle, FWIW.