Charlie98
Member
Later purchased a red dot sight (my first) and found that aiming was easier but my groups remained pretty much the same as before.
From my experience, iron sights and red dots have about the same aiming error on the target, as most dots and front sights are about the same angular width
That's pretty much my spin on it, based on my own experience... comparing apples to apples. I built an AR as my 'DMR' rifle, it has a 1-8x scope on it... I can shoot rings around my other iron or red dot rifles with it. But that would not be a fair comparison, because it was a purpose-built rifle with premium components, shooting good handloads with match, or better quality bullets.
Observations:
1) I had a DPMS 16" carbine that shot pretty well off-hand, but really started to throw shots when rested, or even slung up. Cuprit: The barrel nut was hand tight from the factory. It now shoots as well as my other 16" carbines.
2) I do not expect anything better than 2 MOA accuracy from generic M193 or M855 ammo, or even my handloads with cheapo 55grn FMJ bullets. I get better accuracy with better quality bullets, which, right now, are 62grn Hornady BTHP or FMJ bullets. I consider any NATO-spec 5.56mm ammos to be MOBC ammos... or Minute of Body Cavity. In my opinion, that's what they are designed for; expecting them to shoot like Black Hills or FGMM is foolhardy. Garbage in, garbage out... if you want better accuracy, start with better ammos.
3) My Colt H-bar, with it's 1:7 twist barrel, pretty much hates everything 55grn that I've run through it. It is an anomaly, because my other 1:7" rifles shoot 55grn stuff well enough.
There are a number of facets to accurate shooting with an AR... like someone else mentioned, better sights (red dot or scope) don't help accuracy if there is a weaker link in the chain... improperly assembled rifle, poor quality ammunition, poor quality barrel... or any version or combination of those factors.