As far as the OP's question goes, the Dillon powder dropper being accurate has a lot to do with what powder you are using. Extruded powders like Varget and 4895 can have pretty big variances, more granulated powder like CFE223 and H-335 is usually spot on. Also some of my Dillon powder measures are better than others even with granulated powders, I have 8 of them. I have loaded 308 ammo with CFE223 and Sierra 175gr. BTHP on my XL650 that was under 1 MOA at 500 yards. So it is possible if you use a powder conducive to the Dillion powder measure. I have found my very old Lyman 55 measure dumps the extruded Powders pretty accurately, so when I use Varget, 4895 or the like I use the Lyman 55, just a little slower process.