Yes, I see where they call for a .675 for #6 shot using 3 1/2" on the Kicks web site. But when I tried to add it to the cart it did not come up. Only #4 and #5 shot in 3 1/2" which is a .680. I think the .675 is a typo and should be a .670. Why don`t you give Kicks a call and see what they say. 1-800-587-2779
If it`s not a typo then I would go with a .680 for 6 in 3 1/2". Or drop down to a 3" and go with a .670. That`s what my bud uses.
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