Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
Do you presently have all rope, or rope-to-wire? If the latter, 5/16" rope won't do well in the masthead sheaves, which are sized for the wire. If you're already all-rope, then I agree that 5/16ths is the most common choice (and the one CD supplies).
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.