Help Adjusting a scope

[xtremeairsoft]

I have an NC star tactical 3-9x40 scope. I installed it on my Echo 1 M28 to test fire it and adjust the crosshairs. When I would adjust it a little bit the bb would hit the same spot so i adjusted it more, and after I adjusted the Up/Down a lot it would line up good but the left/right adjustment would be off even though I didnt mess with it. I would have the same problem if I adjusted the left/right a lot, the up/down would be messed up. I have no idea how to fix this, any help would be greatly appriciated.

[Dayton]

It's a cheap scope, nothing you can do about it that I'm aware of. You'll just have to adjust both (vertical and horizontal adjustments) simultaneously till you get things "close".

[xtremeairsoft]

Thank you for the help.

[axisofoil]

If your scope's vertical crosshair isn't perfectly vertical, or your hopup/barrel aren't perfectly vertical, and especially if they don't line up, you will see "coupling" between the vertical and horizontal crosshairs.