I still use many fine older powders. SR-4756 is an ole timer that really has no apparent modern replacement. Long Shot comes close in performance but is more difficult to light in cold weather shot shell applications. Long Shot also is significantly more dense, necessitating the use of a longer wad column. SR-4756 also has a shallower exponential form up to maximum pressure (about 12KPSI) than its more modern counterparts.
Along these same lines, the now discontinued HS-7 is a powder for which I have found no direct modern replacement. There is no other powder that will drive 2.5oz of shot from a 10ga in excess of 1100fps and still keep pressures in the safe range AND still allow the use of commercially available wads without modification.
Like others have stated, I truly enjoy the variety of powders available to the handloader today. Smaller kernel versions of the oldies are a favorite of mine. I especially favor the Hodgdon XXX-SC line for big game and cold weather hunting.
There was a time when blending and classifying powders was commonplace for me to achieve the desired performance in a given cartridge. With only few exceptions, I just don’t have the need (real or perceived?) to do that anymore.
