I'm not big on eotechs..to me the retical is too busy, battery life is too short and I've had them go down on me during a time when I really really needed it. I know DEVGRU uses them with great success, but those are the new damn near $700 optic..for that money I'm running an aimpoint T1
I use aimpoints when it comes to red dots...if I were you I would just order an aimpoint PRO and be done with it
Check out travis Haley's YouTube video on combat zeros before you are set on 100 yards..I do 36meters on all my dot rifles
Bench
You do not mention what model scope, or, types of ammo you are trying to use. Nor do you mention what you bought this rifle for - varmint shooting? Plinking? Home Defense? Or to just look good on the wall? You should have told us what "zero point seems to change allot" is - we have no idea if .16" is allot to you or 16" is allot to you.
I do NRA Highpower rifle competition with my AR-15. This is 200, 300 and 600 yard competition with open sights - no scope.
The idea of zeroing in an AR at 25 or 50 yards is great if you are using this as a home protection rifle.
Generally speaking, a rifle is normally pointed slightly upwards to counter gravity when aimed at 200 to 1,000 yards. At 25 to 50 yards the upward angle is so slight as to be non existant - this means when you are sighted in at 25 you are gonna get a drop at 50 and a bad drop at 100 - and unmanagable drops beyond 100.
Most people will sight a rifle in at 200 yards - this makes it 3" high at 100 yards and 3" low at 300 yards for 98% of all rifles. (Keep this fact in mind for the rest of your life)
Likewise - when you sight in at 50 yards - you can expect it to be 3/4 inch high at 25 yards and 1.75" low at 100........ but at 200 you will see minus 8 inches and it is off the charts beyond that.
My recommendation. Sight your rifle in so it hits 3" high at 100. This puts it close to on target at 200 and 3" low at 300. It will also put it 2" high at 50 and 1" high at 25 - plenty close enough for government work at close range. But - these figures are for 62gr military ammo - yours will vary a tad if you use other ammo.
What's ur take on this?