I started reloading about 30 years ago. I had a friend that was a competitive shooter and he simply gave me his recipe for my .223 and that's all I've ever used for that rifle. I used factory bullets for my deer rifle since I shot it very little. As the years went on ( faster than a greased rabbit) I have started reloading more and more. As far as I know, there are five factors to take into account for the best load for an individual rifle. Primer, seating depth, powder type, powder charge, and bullet weight. NOW my quandary. If I use x brand powder with x brand bullet with x seating depth etc and get a .75 group, how do I get to a .25 group. If I change powder do I have to change seating depth? Primer? Naturally the charge would change. How far and how many bottles of powder do I have to buy and let sit on my bench. How many boxes of primers. It seems endless to me.