dave2pa:
It can vary from gun to gun. Most guns (12ga) will be effective 40 - 50 yards with the 3" rounds. This being said my Mossberg would consistently pattern to be effective on coyotes at about 45 - 50 yards. My 870 Remington could take a fox at about 35 to 40 yards. You need to pattern the gun just as you would for turky hunting. Try different ammo makes and choke. For example: an xtra-full might not necessarily shoot better than a regular full choke with a particular load.
By the way, I assume your talking about effective for the normal predators we hunt. Hard to beat a load of # 4 buck on in close or multiple targets.
Just my opinion on the matter. I'm a conservative shooter thus I will always usually be close enough before I shoot. Incidently, I've only taken foxes and deer (00)with buckshot so I'll let you know how it works on coyotes when I can.
Good shooting and hunting.
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