Starting with Remington 7MM SAUM brass, You'll need:
Redding 7MM Saum Competiton dies(Type "S" match)
.295 and .291 bushings
.264 Expander mandrel
Neck turning tool
NECO case neck lube kit
Use the .295 bushing and run the brass through, necking down. I lube the necks on new brass and the entire case if it's once fired 7 SAUM brass.
The next step is to run the brass through your expander mandrel, with a .264 mandrel to ready it for turning....
Set you neck turning tool at 15 thousandts with a feeler gauge, and turn the necks all the way to the neck/shoulder junction. Use of the moly coated shot to slick up the inside of the necks will really help the process and keep the brass from "galling".
Trim to 2.025" and deburr inside and out....
Prime, charge and seat bullets per usual.
After the initial firing I use the .291 bushing in the sizing process.
Runout has been stellar on the 500 rounds I've processed using this method.
It's been worth every bit of effort.