BOBF, I THINK IF YOU LOOK AT YOUR 15 AND 16 THE GRIPS ON THE 15 ARE SMALLER THAN THE 16. FROM YOUR PICTURES YOU CAN SEE THE SIDES OF THE FINGER GROOVES. THE 16 HAS LIKE A FLAT TOP AND THE 15 DOES NOT HAVE AS MUCH. THE AREA BACK FROM THE TRIGGER GUARD IS ALSO SMALLER.