reticle thickness/magnification for F-Class?

[Texas Solo]

I would not want a FFP scope for F class, I know my Vortex PST FFP scope the reticle is too thick for F class at full magnification.

Agreed, x2. I have the same Vortex PST FFP. I love the scope, but can't use it at full power. I usually back the power down to about 16x and it's OK.
The subtension on this scope is .18

My standard Viper has a plain ole simple cross hair, fairly fine, even at full power. I have the "wide V-plex" ....it's .10....perfect for 600yds.