Sundog. Yes. I have seen loads using
IMR-4320 and H-4831. Some were in the NRA's book CAST LEAD, and there was some in an article in I believe either RIFLE or HANDLOADER magazine. I think it was the latter. The article was by Al Miller, an extremely knowledgeable cast bullet shooter. His article concerned the 30-06, and his attempts to reach full power loads.
Not germaine to the subject huh?
In my opinion, based on better than 40 years of fighting with cast lead bullets
, I would not use any powder slower than
IMR-4895 for reduced loads in a .308 Win. IMR-4320 may be OK, but I have not used it.
I don't shoot reduced loads in 30-30, nor do I shoot jacketed bullets in 30-30. Cast lead kills deer very well thank you very much. I get full power factory duplication loads with WW-748. I use a reduced load in the .308 for practice and plinking and small game. A 170 gr. bullet at around 1800 FPS. Bullets for the .308 are heat treated. For the 30-30, cast of wheel weights and not treated for Winchester rifles and heat treated for a Marlin with Micro-groove barrel.
I also load a 190 gr. cast bullet in 30-30 that duplicated the old .303 Savage in power. I haven't had a chance to try it on deer yet, but is is supposed to be quite a killer on larger game. (I have all 3 of Lyman's ast lead manuals. The first one is a treasure of info gathered when cast lead for hunting was a lot more popular.) Some old timers I have talked too lament the passing of the .303 Savage as they felt it killed larger game better due to the 190 gr. bullet Winchester loaded in it. We'll see.
For reduced loads, you should try IMR-4759. This powder was specifically developed for cast lead. It was discontinued, but enough people squawked so it was brought back into production. I use it in the 45-70 Marlin.