Shooting the AR at the range.  100 yards.  I shot a 10 round string and every shot was about 1.25" high.  After I loaded up the magazine again, I dropped the elevation on the scope down 5 clicks.  Should be nuts on now.  First 2 shots were a quarter inch apart, 1.25" low of bull.  Put it back up 5 clicks and was on.

Next target I really take my time, try to remember everything, breathing, trigger pull, etc.  First 3 shots were in the x-ring.  A guy drove up and I pulled the 4th.  (I like shooting alone and worry when people are around watching.  Its stupid, but I choke like that).  5th shot in the bull.  The guy came up and we started talking.  I'd say we talked for 30-45 minutes.  The last 5 shots of my mag were all high and not tight at all.

After that, I let him shoot a mag at some steel (he was from Chicago and his glock was the first firearm he'd ever owned.  he was excited to shoot the AR and enjoyed it.)  When he was done, I loaded 10 rounds of Black Hills and I was making a ragged hole with a few small flyers.  My best group yet.

On a different day at the range, I shot 10 rounds at 100 then 10 rounds at 200.  The size of the groups was roughly the same.  The 100 yard was slighty tighter than the 200 group.  This would mean that I was shooting much better at 200 than 100.  So, essentially the same thing was happening.  Later strings are much more accurate than the first strings.

Given all of that, it seems that when my barrel is warm, the rifle shoots much more accurately.  Even the Fiocchi shoots much tighter when the barrel is warm.

My question is:  Is it normal that a barrel needs 10 rounds to warm up and be accurate?  That seems a bit excessive both for number of rounds needed and how much of a difference it makes.  I mean 1.25 moa is pretty far off.  Just seems like it shouldn't be that bad.

Specifics that may or may not be relevant:

RRA Coyote- 20" free floating barrel
Shooting on sandbags
Bushnell elite 3200 scope sighted in at 100.
Fiocchi .223 ammo for sight in and general target shooting.