3031 and H335 work well. I'm working through a jug of 748 and it's as good as the next powder. My loads cost me $0.16/round. 8 cents for 55g fmjbt's, 5 cents for the powder and 3 cents for the primer. Never paid for cases because I saved the cases I shot with when I was using commercial ammo plus you can probably pick up more .223 range brass than you'll ever reload at many ranges.

I'm working up loads for my jug of 748. Decent enough @ 100 yards for cheap range fodder and will demolish soda cans or clay pigeons at that range.