My 1995 powder works just fine with my 2018 load data (also 2000, 2010, and 2014) . The powder isn't listed in the Lyman Reloading Manual 45th Edition that was printed for at least 12 years and is considered the "holy grail of reloading manuals" right after Dean Grennell's ABCs of Reloading Metallic Cartridges. Another consideration is that even the Lee's Reloading Manual 2nd Edition has no data for Lee Cast bullets. I have an (out of print ? ?) an RCBS cast bullet manual for RCBS cast bullets, and Speer Reloading Manual has RCBS cast lead bullet data.
I have found acceptable (none of my solutions are perfect) answers to reloading using the Lyman, Hornady, and Accurate Arms reloading manuals. I know which bullet, my preferred powder, primer in stock on my shelf. Now I look for the previous load data I used or "what does the book say?", and start reloading without all these other trivial issues slowing me down. Velocity is measured by my chronograph (not load data) , powder charge is MEASURED by weight, but dispensed by volume, cartridge length is measured, and reloading begins. My charges never approach published maximum charges unless I make a mistake. ONE powder bottle (might weigh 8#), ONE box of bullets (might contain 500), and ONE box of primers (might be 1,000) are at my reloading press. This is my only ABSOUTE rule I never violate. Experience is a strict teacher.
I am the source of group size variation. My guns and my ammo are more accurate then me. Wind is the other big factor, I read a book, not the wind. I missed, so what? I have more than 1 golden perfect bullet in the box. Enjoy your time at the reloading bench, treasure your time at the range. In both places you can be sharing our joy of the shooting sports.