Since the 'Single Six' is not chambered in .45LC I assume you mean a Blackhawk, which takes heavy loads. But then you are shooting deer with iron sights, so for most shooters that means 50 yards max range.
I have had poor luck with H110/W296 in the .45LC with bullets lighter than 260 grains, and like Okie said you do not need that kind of power. The last time I saw an armor-plated deer was over three decades ago back when I used to drink.....
My favorite load is the Hornady 250 XTP over 15.5 grains of BlueDot. That gives around 1050 fps in my short-barrreled BH. This gives reasonable recoil and blast (H110/W296 is terrible in the 4 5/8" barrel!) with great accuracy and excellent performance on deer.
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