If you have any of the factory chokes, start with the tightest one, improved modified/modified if you don't have the full.
I am shooting factory full choke in my 28 and I am blown away by the pattern. Foxtrot 9s, 1.5 ounce 340 in the 10 at 40 yards
In my CZ Sharptail 20 gauge I am shooting the factory full choke and the factory improved modified. Awesome with Federal 8/10s
Have a good one, Bo
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