I have had discussions with 2 accomplished 1000 yd shooters who have very different opinions about when to size and then seat bullets. One anneals and lets his cases sit for least 24 hours , then sizes and lets them sit for a week before adding powder and seating bullets. The other anneals, waits 24 hours, sizes his cases and within a few hours adds powder and bullets. Both firmly feel this gives them the most even neck tension on the loaded round. I am interested in other 1000 yd competitors thoughts on this. Since they both do very well maybe it does't really matter?