I wouldn't worry about the red on the front of that gun. Hell I have 20/15 eyes and I can't see it on the gun when I want to see it!

About the screw on the rear sight... my 835's sights wouldn't go down far enough anyway... I took the thing out and it still shot way high.... I put a 2-7x32 scope on mine.

For some hellacious patterns.... Hevi-13.....209 pellets in a 10" circle at 40 yards. Had to beat it without using 7 shot.