Primers can make a big difference. With the newer more progressive powders like the Reloader line I usually start with magnum primers and it can reduce extreme spread and standard deviation with some combos. I also do this as I feel like I do not need to reduce charges much if any when going from a magnum to a standard primer. This is not a hard and fast rule that magnum primers will produce more pressure but if you are not red lining the loads too much it is fairly safe. I like Wolfe primers when I can get them they seem to be more consistent and maybe a hotter formula, not sure though.

The only time I use Remington primers is in the 17 Rem. they seem like the cup is harder and the 17 Rem. at max loads you want to stick to the formula exactly as any component change can red line an otherwise safe load in the little 17.

Other times I am fairly indiscriminate and will buy whatever is available locally to avoid hazmat charges fro just a brick or two. Some loads seem not to be affected others there can be major improvements on accuracy, but it is the last component that I juggle around when looking for smaller groups.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli