Assuming Rifle, I start with; what is intended purpose of the load?
Targets or steel; and at what distance?
Game; size/type (thin skinned, light boned/heavy boned, large)?
Above dictates bullet selection/weight, projected or required velocity, which dictates powder choices.
What is accuracy requirement? Can dictate Bullet seat depth, charge weight, primer/brass, extent of case prep necessary..............
A true "Gun Guy" (or gal) should have familiarity and a modicum of proficiency with most all firearms platforms.
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