A typical ironsighted AR, a properly built one to gov't specs is still only expected to be a 2-3 MOA rifle.
While your groups aren't pretty, as you said, you're new to the AR. I could probably do better, but I've been shooting irons of all types for nearly thirty years, and the AR platform or related (M1, M14, M1 carbine, M249, M240) for anywhere from 5-20 years, so I'm quite familiar with them.
Given a good lot of ammo, properly built rifle and a decent shooter, 1-2 MOA is pretty good for most guys with irons.
Using a match built rifle, a special small aperature, handloaded, heavy long bullets single loaded, a guy at Camp Perry shot minute of angle at 1,000 yards with an AR.
That's a 10" group at 1,000 yards. Still inside the chest of an average man.
Scopes don't help you shoot better, they reduce the complexity of what's going on (single focal plane) and help you SEE better. Back in the day, guys in the national/international shooting comps with irons and good eyesight did some insane things with rifles and irons. Quigley Down Under is a movie, but not far off what some guys pulled off.
"And Shepherds we shall be. For thee, my Lord for thee. Power hath descended forth from thy hand, that our feet may swiftly carry out thy command. So we shall flow a river forth to thee and teeming with souls shall it ever be. In nomine Patris, et fili, et Spiritus Sancti. Amen."