A bear den gun? Some authorities argued that a shotgun is better then a double rifle to shoot a bear roused from the den, because, at the point-blank range typical of the situation, accuracy is unnecessary, and the quicker aim down the rib without the rear sight is an advantage (remember, Buturlin advised to do away with the front sight, too). Could there be a deducated smoothbore rear-sight-less slug gun? Just a guess.