I did some work with Power Pro Varmint with the 200TTSX in my 35 Whelen AI and it was most impressive - pushing 3000 fps. Perhaps it'll work with the 200 AB as well.
I bought a bunch of the same 200AB seconds as you from SPS but mostly figured to try them in the .358 Win, since I am "there" in the Whelen with the 200TTSX and Varmint. I posted my work on another site, let's see if I can find the link.
200 TTSX and Varmint
If you scroll back from the linked post you can read about the initial interpolations to derive the data and tests with 200 grain round nose to baseline the charges.

Good luck,
Rex

Last edited by TRexF16; 07/01/20.