Won't group at 100 but will at 200?

[Steelhead]

With my limited ability 200 yards makes the most sense to do load development/testing. If it shoots at 200 it will shoot out to 1k, not always so with a load that shots tiny groups at 100.

Not quite true.
After about 600-700 your ES will come into play and by 1000 it's quite important.
At 200 it's not even a factor really.