I want to use my .410 shotgun with 3" magnum slugs to hunt coyotes. Would this be a good idea? any ideas on distance?

unless its rifled you will be able to shoot......oh well... ten feet accuratly

I would check my states regulations on carrying and using slugs in ky it's illegal to carry a slug except during deer season.If it's legal just check and see how good it will shoot them,if you can hit a 4"circle you can kill a coyote at that range whether it be 20 yards or 80 yards,some shotguns will shoot different ones accurately and some of them you should just unload the gun and try to get close enough to club them to death with the gun,just kidding but some shoot that poorly with some types of slugs.Good luck and you may have a good shooter!!

my boy shoots them in his mossberg and they r good to 40 50 yards no problem

I never used a shotgun but I imagine a 410 can't have the best range so you'll be bringing in a coyote pretty close but I think if your confident with it you should try it but I would want something with more range if I was in the situation.