Start by getting the reloading data from Alliant (used to be Hercules) - they're the folks who produce Red Dot. Then, with the Premier/STS hull and a 209P primer, choose the wad & powder charge that will give you about 1180 fps.
A couple of things you might want to try... If you check the data, you'll probably find that you can use a slightly lighter powder charge if you use a hooter primer - Winchester or CCI primers are both "hotter" than Remingtons, and Federals are hotter yet. Also, I shot Red Dot for years (many, many years) and switched to Hodgdon Clays back about 1995, and I haven't looked back; Clays is much cleaner burning. I dont shoot an auto, but I know several guys who do, and they've switched from Win Super Target, Red Dot, or 700X, and they've all stayed with Clays.
I punched the STS hulls, 209P primers and Red Dot into the recipe maker at Alliants website. There were 23 recipes. So, I suggest you do the same at http://recipes.alliantpowder.com. If you also included a brand of wad, I could have come up with just a couple.
Here's two using Duster wads (i haven't tried them yet, but others here seem to think their great):
Rem. 209P, 17.5 grains Red Dot, Duster Green - 1,200 FPS and 10,000 PSI
Rem. 209P, 18.5 grains Red Dot, Duster Green - 1,255 FPS and 10,900 PSI
I generally use Federal 12SO wads. Here's three recipes:
Rem. 209P, 18 grains Red Dot, Fed. 12SO - 1,200 FPS and 9,000 PSI
Rem. 209P, 19.5 grains Red Dot, Fed. 12SO - 1,255 FPS and 10,600 PSI
Rem. 209P, 20 grains Red Dot, Fed. 12SO - 1,290 FPS and 10,500 PSI
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