I am introducing myself to iron sights on my M4gery. What kind of groups should I expect as a minimum/maximum? Model 1 sales kit, win q3131 lot #sc81, prone hand supported with beat up m16 sling. at 100 yards 95% are on a 6"
shoot n see but i can see what look like 1.5" sub groups. I may put on an A2 stock for better cheek weld. any tips fellas?

I wouldn't worry to much about the group you shot. What kind of groups was the rifle shooting before you tried the open sights?

Previously I had a scope on it but it lacked sufficient rings to allow for proper eye placement and consistent cheek weld. So with that and the fact that I had no experience with standard iron sights I decided to jump on in. The pattern I described is a group from a 30 round magazine not 3 or 5 round groups, if it matters. TIA

You have too many variables with no standard.  Put the scope back on, get your cheek Mig welded on and shoot the gun on a rest to see your "standard" group.  That will be the group by which you measure your iron sight groups.  

THEN you start taking 5 shot groups and measure them, not 30 shot groups.  I'm guessing here that you took 30 shots relatively quickly? (within 15 minutes)  

You need to cut down on your variables and answer your own question.  If you are asking what kind of groups we've received, then I can tell you that shooting my friend's M4gery, I had about a 1.75" group at 100 yards with american eagle ammo.  Looks like you should get your equipment in line with your shooting before you try any of this though.  Unless you are in close quarter combat, I'd chuck the stock in favor of the A2.  That's how all my rifles look and they all shoot like bolt guns!

Good luck with your setup, I hope you tune it they way you want it and get better with the irons! (Keep in mind those 6" groups open up to 12" @200!)

My hope was too see what most folks can shoot with the iron sights and the short sight radius. The other day I got to the range just as the rain did so I only got to shoot 2, 3 shot groups which were less than 3 inches. I know some folks claim that they can shoot sub MOA with irons so i figgerd I'd ask.
Also how much shorter/longer is the A1 stock compared to the A2?

With my BM carbine (16" barrel) I average about 3" for 5 shot group at 100 yards.  I do just a little better with my 2001 LEGP. When I put the red dot sight on these carbines I can do under 2". This is with Winchester Q3131A or UMC and not "match" ammo.  With my 2002 LEGP I was getting about 2" for 3 or 5 shot groups with same ammo.  Personally I don't think I can do much better than 2" due to failing eye sight.  

I could shoot 1MOA with a new Bushmaster 16" and iron sights.  I say "could" because I traded that gun.  I haven't taken the time to shoot groups with my current ARs because it's too damn cold.

Edited to say that my eyesight is going downhill so I may never do it again