big country is right .rifled bbls.are for single projectiles only.smoothbore slug bbls. are cyl or imp. cyl choke make fine rabbit and upland bird guns,if you can get use to shooting over the iron sights.squirrels are tough i generally use a 20ga. 23/4 .full choke 5or6 shot.no offense intended in va.squirrels are way too fine a game animal and too fine eatin to be refered to as "tree rats'.GOOD LUCK,SAFETY ALWAYS!