Successful load for optima

Since getting my .50 cal optima last winter for a elk hunt I've been playing with many conical bullet styles as I would rather shoot my own cast than sabots though I have a pile of power belts, knights tc and precision rifle sabot combos I just cant bring myself to  use a proprietary  product at today's prices. So the molds I'm working with are Lyman Great plains 397gr,  LEE 459gr .501GC, LEE 460gr .515RN and a Accurate 415i bullet all sized to .503 except the .501GC . Using T73f @ 80, 90 and 100gr weighed w/.54 op wad after 3wks 40-50 shots ea wk end my results were all over the place the 209s were Remington ML 209s so today I tried using off brand RIO 209s man what a differance that made.
With 90gr t72f or 3f, .54 oxyoke wad, lee 460gr RN and RIO 209 primer my 50 yr group is 2+", 100yd is 3+" and 150yd is about 4"+. The sights are William's Ghost ring fire sight  which  really helps considering these 62yr old eyes. If you dont cast your own there is always Bullshop and No Excuses both will size bullets to your requirements.
Oh and another thing I literally used a sand bag on my shoulder for every shot after the first weekend of 50 shots it's a good thing no one was around to see a grown man cry