Thank you Sir.Bill, I do three shot groups going up in .3 gr. increments. You can make a case for .5 gr. increments and then narrowing that a bit more later. But with the short range of weights from min-max in a 30BR, .3 gr increments gets me the info I need with fewer shots after it's all said and done.
One of the best 30BR shooters and tuners I know does .5 gr. increments.