Hello everyone.  I just wanted to ask those more AR experienced than me about this.  When sighting in my new AR 16in bushy A3 w/ carry handle I noticed the Olympic 55gr I have will consistently not group as tightly at 25 meters as the Walmart value pack Winchester 55gr value pack stuff.  At 25 meters the Olympic groups all over a 3 inch sticker target with most shots roughly center.  The Winchester groups generally in a really tight group dead on center within a 1/2 inch if I am doing my part.  Is this to be expected?  Also, I have seen a rough spot in the chrome lining of my barrel, still there after approx 1000 rds with no change, about 1 inch from the muzzle in the side of one of the lands.  The top surface the bullet touches on the rifling (the land) istelf appears to be OK and smooth, but the rough spot looks like a small chipped spot in the edge or side of it.  Do not know why this happened, it was there when first purchased (new) and before cleaning it.  Would this negatively affect my accuracy?  Thanks in advance for replies.

82 feet ain't a good distance o judge ammo accuracy. 100 yards is good, with 200 a little better.

In my gun (RRA CAR UTE) Winchester white-box (Wal-Mart 55gr 40rnd value packs) was far and away the WORST grouping ammo that I've tried, out of 6 different brands, & 2 bullet weights. My shooting was done @ 100yds. Of course, YMMV...

I agree, you need to stretch it out a little more than 25 meters.  However, I tried the Olimpic SS109 and my only thought was "this stuff sucks big time!"  Accuracy was around 4" @ 100yds and FTF's about every 5-7 rounds.  I was very disappointed by the Olympic ammo.  This was about 1 1/2 years ago, so maybe their QC has come up a bit.  
Sleepy717

Edited to add that this was out of a Bushy 20" HBAR that shoots XM193 around 2" @ 100yds.

Just for reference, based upon your tests, what did you find to be the best grouping ammo? I'm just starting to shoot my AR on a regular basis (300-400 rnds every 2 weeks) and I've been using the very same Winchester White box ammo.

At 100 yards I got one inch groupings with the Winchester Value pack. [%|]

Dont ask, it was from a 16 inch bushy, chrome lined.

I sure buy a hella lot of it though.

Of the bargain ammo that I buy the winchester shoots the best.

Winchester-1.5 inch at 100yd
PMC-3 inch at 100yd
Wolf-Minute of paper plate at 100yds
haven't tried Olympic, probably never will
Q3131-2 inch at 100yd
XM193-2 inch at 100yd
guatamalan surplus-1.5 inch w/ one flyer (like this stuff)
68gr hornady BTHP reloads-0.4 inch at 100 yds.

I have gotten 1 and 1/2 to 2 inch groups at 100 yds out of my Bushy 16 in chrome lined with the winchester value pack as well, but the olympic groups so bad at 25 I am hesitant to even try it at 100.  Probably wouldnt hit the paper, much less the target.

You CANNOT judge the accuracy of different ammo at 25 meters. Shoot for groups at 100 yards.

[url]http://www.ar15.com/forums/topic.html?b=3&f=16&t=161027[/url]

*EDIT* I fixed the link...

Thanks Russ. I actually read your post and it totally slipped my mind. Thanks again for the info.