Originally Posted by
sauer14
Question, when using a crony what do you look for? do you want all your loads to be with in a with in a certain speed? If so what is an acceptable variance? 50fps, 25fps. If the bullet speed is very close does that mean your loads are more accurate?
Read up on ladder testing for load development. What you are asking is the general premise there. If you have a large ES or SD, your groups will tend to string vertically. By ladder testing, you can identify the most forgiving range of charge weights to produce consistent muzzle velocities and regular accuracy. In other words, if your ladder test shows 3" difference at 300yrds from 28.2grn to 28.4grn, but then only a 2" spread between 28.8, 29.0, 29.2, 29.4, it makes sense to load 29.0grns and then play with your coal to get group sizes you like. At 28.4grns, a small mis-weigh means 1" difference in impact. At 29.0, a much larger margin for error in charging yields far less effect. It also lets you know when more powder doesn't give you any extra velocity worth something, so you can save a ill powder cost.