The Lyman Cast Bullet Handbook #4 shows " all bullets sized to .429" dia. " which I thought odd untill I saw the test gun was a Universal Receiver not a real revolver . For a revolver I would start at .430 , which is .001" over factory jacketed bullet dia. and if I were placing the order would get a .431 H&I die while I was at it .
The reason being Lyman H&I dies may say .430 on the die but , depending on a few factors , you bullets may come out a little larger , a little smaller and sometimes , occasionally , right on the money .

A tale of Lyman .357 Die and .358 Dies ...
The .357 die sizes bullets to .3575 ... a little over
The .358 die sizes bullets to .3579 ... a little under

The difference is only .0004 between the two . Not really enough difference to matter in actual shooting test .

Oder your H&I dies then measure your sized bullets and see what you actually are shooting . I never measured the .357 sized bullets until after buying the .358 dies ... and found no difference in accuracy .
Gary

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