A lot of the comparison on what is accurate has to do with what various opinions are, and the type or power of your optics, and distances involved.

I know that in the 80's, the Ohio NG rifle team had some shooters that with match M-14's with match sights and match ammo could do 10 shot 1-1.5" groups @ 200 yards (I think that is pretty darn good!) That is in position shooting.

From a rest on a solid bench I have bolt action 223's and 308's that will do dime size groups at 200 yards. While nice and somewhat impressive looking, I was only doing a good job. A fantastic groups under the circumstances, would be a group where the outside is measured,and the diameter of the bullet is subtracted. The 5 shot group size should read something that starts .0 or maybe .1! (I used to produce these on occasion, but I believe the eyes are a little weak, and the muscles a little shaky now)

It only takes 3 good things to produce these type groups. 1) A good rifle w/good sights or good scopes, 2) good ammo, and 3) a good shooter! (Good weather is helpful but not necessary!)

Number 2: Good ammo, weather factory or handloaded is determined by consistency and concentricity (No wobble as it rolls across glass). Brass fired only in one good gun then Neck Sized, was the old standard to achieve concentricity (and still works). But some of us have a thing about ammo not fitting a rifle chambered for that round. So I Full Length all my ammo! It will fit and fire in any rifle with that chamber! I often only size the neck 2/3 of the length for concentricity, I also use competition seating dies That seat the bullet on the same axis as the case. (if you thought that was a given, you will be surprised how far off things have become.) This is a compromise, Bench Rest chambers .002" diameter larger than the sized case are the best, but don't always work in the field.

Consistency, is a factor of exact duplication of components from one round to the next. So if all your bullets, primers, powder charges and cases are the exact same, they will perform the exact same in one rifle. The next gun may OR may not like that combination. (For example of not liking something, IMR 4064 is reported to be the best 308 Win powder. I have had 12 rifles in the last 40 years in 308, not one of them liked 4064!) My rifles like Varget and they like IMR 3031. So your award winning ammo may not shoot well in my rifle! Or mine in yours! BUT 12 in a row is way outside the bell curve!

Ivan