I’ll be the first to admit that I’m ignorant when it comes to ar’s, but someone tell if this is normal.
Using sandbagged bench rest I am dead on at 25 yards, 2" high at 50 yards, but here is the problem.  I am 6" high at 100 yards, where does it come back to zero, I thought it would have been 100 yards.  

Gun: 16" barrel w/EO sight, mounted on a flat top receiver.  Ammo used was Federal 55 gr. FMJ.

Thanks for any help.
ScubaTexas

Actually it sounds about right.

With a 50 yard zero yer closer to being on at 100 but won't actually be "on" you'll be "on" at 200 meters or about 220 yards.

If your zeroed at 25 yards your bullet trajectory should be right on at 300 yards. If you want to have a 100 yard zero then shoot and adjust at 100 yards.

click here and read up

Quoted: I am 6" high at 100 yards, where does it come back to zero, I thought it would have been 100 yards.

You are shooting a 223/5.56 and not a slingshot, right?

Your line of sight stays level, while the bullet is traveling up and will not hit its peak and come back to your line of sight untill around the 300 mark or a little further (with a 6" 100yd zero).  Gotta remember the arc of the bullet vs. your line of sight.

Try putting it on a 50yd zero instead (for plinking purposes) it will probably better serve you better for blasting.

Thanks that is what I needed.