All things considered the more consistent your load the more consistent your results should be. Hard core blood shooters shooting their top scores weigh their charge, have copper tubes to load through so an grain of powder doesn’t stick some where in the barrel, false muzzle and other tricks to make sure their loads are as consistent as humanly possible. Shot in a vacuum x load should produce x velocity and follow the same path with mathematical precision. Just Newton on the bench.
In real life warm day is different than cold. High humidity differs from low.
Still the more consistent the better.
On a traditional rifle the sights are crude. We are loading by volume, spit at the range or a better lube on a hunt. Patch one may be lubed more then patch two, or less. Even if you swab the bore your never as clean a your fist shot.
Constancy counts, big time.
Yet in near fifty years I never weighed a ball.
They have made scales accurate to a tenth of a grain for centuries, but you don’t see them in trading list until the gold rush. And they weren’t used for base metals.
I inspect the ball. Is it frosty or wrinkly, do I see an arid hole? Back in the pot.
Clean and smooth, in the bag.
That said folks who weigh ball no doubt will out shoot me. That’s ok.
What counts to you?
Are you happy if your palm covers your group? Vs are you unhappy if your thumb covers your group but not your pinky.