Yeah I hadn't really considered how much that speed is gonna close down those pin gaps. LOL

Here's what you do:

Work backwards with your longest pin first. If you want it to be 43yards set that one to 43.
Then set your gaps to where you are comfortable seeing through them properly, and simply figure out what those yardages are. LOL
Heck I don't know, I just make this stuff up as I go along anyway.

At 300-308 ish on down they work great........325-350fps could be a problem.