First Build Having Grouping Problems

[mdewitt71]

So many factors could be at play... hard to diagnose over an internet post.
Did you try a group off of bags without the lead sled?
Are you sure your scope is tight?
Are you sure your barrel, hand guard, and receiver are tight?
Did you reload the ammo or get it from someone?

like 1911man stated, I have shop Milspec triggers for 30 years, I would not blame them on that big of POI shift.
I would not even spend the $$$ on a new trigger till I got this POI shift figured out.

I am interested in hearing what the cause is/was....

[AZBackcountry]

If you are still having grouping issues after trying all the great advice, I would swap scopes. The reticle could be shifting even on a new scope. I assume that you have already looked at your rings to see if the cross bolts aren't bad since you know to torque them. These are usually issues after years of hard use but worth a look.

[howl]

ARs are not as easy to shoot well as regular bolt guns. Make sure everything is tight, shoot off front and rear bags instead of lead sled, get hand from around back of the pistol grip when firing. Your ideal, which I never get 100%, is to fire with the rifle tracking straight back. The vertical crosshair should stay in the middle of the target, while the horizontal will move up. If you're set up right, you can just push it back with your shoulder and come right down on the center. I spend more time setting up the bags and sliding the rifle to make sure it's set up right than I do taking shots. Breaking shots is easier than getting it all set up correctly to shoot the best groups.