Got some help at the range:
Finally at 120 yards I could group as required, I still have some right side deviation but the grouping is good.
I will use this AR-15 for the match Septembre 23rd. in Roanoke.
I used regular Remington ammo .223 55grain full metal jacket.
The weird thing was that when I tried to shoot my Glock 35 I found the problem I had on my first match and why I could not hit any target sitting in front of me, the aim was totally out of sight for my application, I had some help from the range manager he asked me if I wanted to let him do it and he fixed my sight with 3 rounds shot, the beauty of the Glock 35 is that you can modify bot axis x and y on that sight.