Torquing the rifle to line your post up, which may or may not be what you meant, will introduce inaccuracies. The aim of the game is to make a straight line out of your dominant eye, the centre of the ring, the front post and the target; with as little confounding force exerted on the rifle as possible.
Generally, if your post isn't lining up with the centre of the ring, your body is in the wrong position for the shot. There's a natural point of aim for how you're situated when you set up. You can find out whether you're messing things up by aiming your rifle at the target, closing your eyes, putting your rifle down, and picking it up again into your shooting position. When you open your eyes your rifle should be pointed in more or less the same place. That's the natural point of aim for how you're lying.
If you're having trouble finding the centre of the ring - well you're never going to get the exact centre. It's possible your eye is too close though. Could always try sitting a little further back from the thing and see whether you find it any easier that way - though obviously don't fire the thing unless you've got it against your shoulder. If you find it easier, you may be better off adjusting your stock a little.
Oh, and focus on shorter range stuff first - and shooting a consistent group rather than shooting to the dead centre of a target. The real key to shooting is having the patience to keep everything consistent. Once you're consistently missing in the same general area every time you can adjust your actual aim relatively easily. You're likely getting no information about just how you're missing if you're shooting single shots to a 1000 yards out. I doubt very much it can even be done in any meaningful way with your rifle.
Way back in 1964, I went into the army and qualified "Expert" with the then-standard M14. With my young eyes and steady body, I could pop those 350-yard "trainfire" sillhouettes without any problems using the iron sights on the 14.
I had trained my rifle shooting primarily with a Benjamin pellet gun, a .22 pneumatic model which I had literally put thousands of rounds through.
I practiced all the standard positions and it served me well.
Fast forward to the present. A few years ago our department decided to get "patrol rifles", a standard AR platform with the EOtech optical sights.
We had to zero these rifles with the iron sights and get the EOtech shooting to the same POI.
My first look through those iron sights with my now-much-older eyes was a bit of a shock... I could hardly get a good sight picture at all.
There were two front sight posts, for instance... One over the other.
Kind of scary to see how age creeps up on you.
Fortunately the optical sights work terrifically.
Make sure your sights are zeroed. Google this, it's hard to explain.
Zero your rifle at 36 yards. This is the same ballistic point as 300 yards for 5.56.
Then, practice dry firing. Keep in mind,
Rifle butt into the high pocket of the shoulder.
High, firm pistol grip
Cheek firmly welded to the stock
Eye relief (distance between your eye and rear sight aperture) so its comfortable.
Sight alignment: TIP of the front sight post centered horizontally and vertically in the rear sight aperture.
Sight picture: BLURRY target, CLEAR front sight post.
Now, breathe in, breath out, pause and
Slow, steady trigger press, being careful not to push or pull the rifle.
Don't anticipate the break, and be prepared to hit money!
And I hit man sized targets at 500 meters ;)
I like this zero better
This makes for a very flat trajectory out to 250 yards, with less than 2 inches of rise and drop.
but thats for a 'patrol' or other sort of defensive rifle. For longer ranged riflery, simply put, you should just zero to the range you are shooting at/