I usually use Herco powder for all my loads whether they be 7/8oz or 1oz loads. Sometimes I will use Unique for 7/8oz loads and for my 1oz loads in the STS case I prefer to use Blue Dot. My favorite load for the Rem STS cases consists of:
7/8oz
CCI209 Primer
17.5gr Herco
Rem RXP wad
1200fps
9,400PSI
Another favorite 7/8oz load for this case is:
7/8oz
CCI209 Primer
16.5gr Unique
Rem RXP wad
1200fps
9,900PSI