Inside 40 yards I'd look seriously into BB's. Hornady makes a predator hunting load of Lead BB's. I use an ounce of NP BB's in my 2 1/2" 16ga drilling for coyotes and 1 1/4oz of the same in 2 3/4" combo guns for coyotes. Shoot the full choked barrel.
BRNO combo 12ga/22 Savage Highpower
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Wilkes drilling 16ga/16ga/6.5x58R