I've shot a fair amount of 200 gr cast with 10 gr AA 2. Works for a moderate magnum load, just have to be super extra special careful about charge weight. 2 meters great so it's more making sure the scale was read right on the test throws and don't double charge.
For an extreme example of small charges in big cases, I've made mouse loads in 30-06 with 6-8 gr AA 2 and 180 gr cast bullets. Grouping isn't bad at all, with a little work I could get under an inch at 25 yds.
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