Kwatson.....
About the only absolute in cast ballistics is,the bullet MUST exit the barrel. Other than that,gonna be hard pressed to put any sort of "must do it this way" theories into practice.
Just got my Sata newsletter yesterday.
Think of a modern paint spraygun. And all the adjustments available to the user. Here's a list....
Tip design,tip/needle size,fluid knob,air knob,fan control,hose size,connector size,air #'s from compressor,how clean is the air,type of paint,viscosity,pot life,angle of attack,ambient temp,drying temp,humidity.
That's most,prolly missed a cpl.
Some guy on the intertube says "must be 2 turns out on the fluid knob"..... positively won't work if it ain't "2 turns out". The guy is a pretty good painter but that is complete bull sheet looking at the larger picture. Yeah,2 turns out with about 10 other things in sync sure.....
There are simple "answers" and then more complex answers. The depth of which has a lot to do with the effort in which the question is presented. And don't take that personally cause it ain't about you.....
That's about as concise as I can put it. Somebody else may explain it WAY better. Good luck with your project.