SR4759 is/was a really truly great powder.
It was always more of a specialty item, though. If you're into cast bullets in bottleneck cartridges, it is/was usually one of, if not the best choices.
It has an unfortunate history of spotty production, regularly discontinued without warning.
I've used it for a bunch of cast bullet loads in old "mil-surps" such as Lee Enfield, Swiss K-31, Mauser 98, etc.
It's also great for silhouette pistol, if you shoot T/C contenders in cartridges like 30-30, 357 Herrett, etc. (again, with cast bullets)

One of it's great virtues is it's predictability, stability and safety in low pressure loads. Pressures build slowly, so working up loads is no problem, at least if your goal is mild cast loads.
For virtually any 30 cal bottleneck cartridge, once your velocity range is roughly 1250-1450 fps, you'll get good results with 150 gr. gas check bullets.
I've found 14-14.5 gr of SR4759 to be a good place to start in 303 British, 308, 30-06, 7.5 x 55, etc.
If you like plain base bullets, drop the load down to maybe 10-12 gr. Velocity goal should be lower than for gas checks.
What worked for me might be different for you, so play it safe! There's tons of data out there for specific cartridges.
I've heard of people going higher, and use SR 4759 for jacketed loads, but I think there are better choices for that.

Best Regards,
Jim

PS: Usual disclaimer for load data. Use at your own risk.