I don't shoot at 1k, yet. But, I have a rifle dedicated to it.
After talking to several experienced LR shooters on another forum, my brass prep for that rifle is:
1: Open new box of Lapua brass
2: Run mandrel in case mouth.
3: Load and shoot.
Lapua brass is absolutely perfect, out of the box.
Dies are Redding type S F/L bushing. Seated .005 off the lands.

My other precision rifles, I use Redding Type S full length bushing dies. Brass gets prepped on a Lyman prep center, including flash hole deburring primer pocket uniforming, deburr/chamber. I trim it all with a Forster trimmer.
I use Imperial sizing wax, and wipe it off after sizing, I don't want my freshly prepped brass banging around in a tumbler! I use regular Hornady seating dies, with the floating sleeve, and measure with Hornady LNL bullet comparators.