XS banded sight shooting 11in low at 25 yrds

[caygeon]

Hey Guys.
I put a banded XS sight on my baby griz and now it shoots 11in low when I line the rear up with the bead,Any idea how to fix this?
I really like the sight but need it to shoot about POA.
Thanks for any input.

 

[Leg]

You installed the XS sight on the front, what are you are using for a rear sight? If the difference in elevation is too great between the two there might not be much that you can do except replace the rear with the XS unit designed to work with the front or replace the front sight blade with one that's the proper height. Have you adjusted the rear sight at all?

 

[caygeon]

Well looks like I got to go buy the XS front sight,I was hoping I could get away with just the rear cause it was shooting a little high.Thanks for your reply.I think I might try putting the rail back on an sighting with that,It should bring the rear up some.
Thanks again

 

[Leg]

I'm confused, the banded front sight is a front sight.

 

[Boomer]

What style of rear sight are you using? Clearly, the front sight must be made lower or the rear sight higher. My experience with XS winged barrel band front sights and ghost ring rear, is that they compliment each other well on 20" 870s, and shoot POA, over typical shotgun ranges. Your shorter barrel might be the problem, but regardless of the reason, you have to find a way to balance the heights of your front and rear sights.

 

[caygeon]

I need a rear sight it seems,I have a rail that came with the Grizz so possibly I can find a low profile ghost ring for the rear sight.
Thanks for the help

 

[easy]

I have a formula to figure sight radius, sight height and POA to POI. I'm sure you can tailor this formula to meet your 870s sight height needs. It will be easy to establish which sight to replace ... front or back. Good luck.

M = S x D ÷ ( R x 12 )

Where:

M = amount of movement or change in sight height needed (in INCHES)
D = distance needed to move the bullet's strike to hit point of aim
R = range to target (in FEET)
S = distance between front edge of rear sight and rear edge of front sight blade (sight radius in INCHES)

Example:

Your sight radius is 5.7 inches and you need to move the bullet's strike 3 inches lower at 25 yards (75 feet):

M = 5.7 x 3 ÷ ( 75 x 12 ) = .019

Thus you need to raise the front sight (or lower rear sight) by .019 inches.