AR 15 Accuracy Expectation


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Dobe66
May 29, 2009, 12:30 AM
Recently picked up a "custom" built AR-15 with a 1/9 20" free floated SS barrel, unknown who milled the upper, Mega lower with a Giessle trigger installed, and Harris bipod. At 100 yds the groups varied from a low of just under 2" to over 3 1/2". Traded out scopes at one point to see if the first had a problem (Busnell Elite 3200 then 4200). Similar results with 3 different shooters, commercial and reloaded ammunition (55gr FMJ, 69gr and 75 gr Match BTHP). Very little, if any, wind during all tests. A little over 100 rounds so far.
I recognize there are a lot of variables to consider and there is no pat answer. That being said, did I have too high of an expectation for accuracy or is this what one would expect? What should one expect?

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benzy2
May 29, 2009, 12:36 AM
Assuming you are shooting off a bench with proper technique it sounds about right for FMJ surplus/blasting loads but a bit big for match reloads. I had to do a bit of looking though to find a load that held MOA out of my AR but it was out there. I don't know how much work up you did on the hand loads but if you didn't test and work up for this rifle there certainly could be a bit more left in the rifle. A few loads I had that shot good in one AR printed about 5" in another so they really are individual creatures. I would try a few more powders and bullets and see where that gets you. I wouldn't expect more than that though out of a lot of the cheap factory stuff.

Matrix187
May 29, 2009, 12:45 AM
I get about 2-3" with my del-ton ar15 20" HBAR /w eotech at 100 yards using 5.56 surplus. Good enough for me.

Lloyd Smale
May 29, 2009, 07:33 AM
most of my ars will do about 3 inch with ball and an inch or less with good reloads they like.

Boris Barowski
May 29, 2009, 07:37 AM
maybe try some 52gn ammo, 75gn might be heavy for 1 in 9"
reload and try to find what it likes is all i can say :s

flipajig
May 29, 2009, 08:01 AM
I found this on a web site for SHILEN BARRELS
8'' for 70grn and up
9'' for up to 70grn
12''for up to 63grn
14''for up to 55grn
this info is for .224 cal only hope this helps

Bartholomew Roberts
May 29, 2009, 09:21 AM
What Boris said... 1:9 can be iffy on stabilizing the 75gr BTHP and if it doesn't like the 75gr, it usually doesn't like the 69gr much better, based on my past experiences with 1:9 barrels and both loads.

I would recommend trying some of the 55gr Hornady loads. They are consistent performers in all of my rifles and I would expect to see MOA or even sub-MOA performance out of the rig you mention and this ammo. If you need some cheap test ammo, I've also had good luck with the 52gr JHP sold in bulk at Wal-Mart for varminting in the past (but haven't used that load in several years now).

HJ857
May 29, 2009, 09:34 AM
I would expect better from that setup. Try again without the bipod and using bags front and back to see what happens.

Just as a comparison, using my handloads with 69g Match Kings my Model 1 NM upper will shoot 1.5" with irons at 100yds and 5/8" if I use a scope at 9x.

My Bushmaster M4 style upper with handloads using basic bulk 55g soft points will shoot no more than 3" with a 4x scope at that same distance.

alpha6164
May 29, 2009, 09:40 AM
I would definitely stick with 55-69 grains. Get some match ammo. And i hope you dont take offense to this but 80% of these issues are the shooter. Now if you can shoot 1MOA or better with another rifle consistently then you can rule yourself out. But just because two other people shot the AR does not mean that they are any better shooters. You can also find a friend or someone from the range that can shoot sub-MOA and have them shoot it to rule that aspect out. After than only i would start chasing equipment issues.

Dobe66
May 29, 2009, 11:56 AM
Thanks everyone. It looks like it's back to the drawing boards to find just the right load and bullet for this particular rifle. Went with the 1:9 twist because I thought it offered a good range of bullet weights that it could handle thereby offering a potential for a 300-400 yd shots. I'll guess I also need to try the lighter bullets as well.
Forgot to mention that we tried shooting on rifle rests/bags as well as using the bipod. Actually there were 4 shooters but I discounted one's results, even though they were about the same, because he doesn't consistantly shoot less than an MOA with his other rifles.

bmwguy
May 29, 2009, 12:05 PM
Wow, I should consider my lucky.

I recently received a WOA 20" varmint upper after a 5 and 1/2 months wait from White Oak Armament. I paired the WOA upper with a CMMG lower with harris bipod 6x9 and a Gessele match Trigger. It also has a Mueller 3x10x44 on Larue LT-104 mount.

I'm getting 1/2" moa All day long with my reloads(running 55 gr vmax with 22.6 gr of Hodgon H322). With surplus ammo, I'm getting 3/4".

http://i163.photobucket.com/albums/t290/bmwguy2007/ar15v1.jpg
http://i163.photobucket.com/albums/t290/bmwguy2007/ar15v2.jpg
http://i163.photobucket.com/albums/t290/bmwguy2007/ar15v3.jpg
http://i163.photobucket.com/albums/t290/bmwguy2007/ar15v4.jpg
http://i163.photobucket.com/albums/t290/bmwguy2007/ar15v5.jpg

bmwguy
May 29, 2009, 12:15 PM
You may want to check to see if your receiver is trued and also check the torque on the barrel nut. If the ar15 upper receiver is not trued and the torque is too high, it will cause some inaccuracies.

RP88
May 29, 2009, 01:38 PM
the number I've seen for a stock AR is something around 1.5-2" with decent ball ammo. That number opens up with crap ammo, and closes with FF tubes, better barrels, and match loads to sub-MoA depending on how much money you put into it (and how good you are). My Del-Ton I had shot over 2" with PMC ammo, and my CMMG AR shoots PMC a little less than 2" or so off a bench. Both were your everyday "fight-ready" ARs, and not hunting/varminting/match rifles.

rcmodel
May 29, 2009, 01:43 PM
You might try cleaning the crap out of it with copper solvent.

Could be copper fouling getting away from you on a new SS barrel before it smooths up from shooting.

rc

JDGray
May 29, 2009, 02:54 PM
3" groups are good for 300yrds:D My RRA 20", 1 in 8" twist likes 60gr boolits best. Hand loaded ammo will get you well under an inch, if you do your part, at 100yrds, unless theres something wrong with your gun. The same rifle that shoots 3" 300yrd groups, has also shot 3" 60 yrd groups, with some junk Win 55gr fmj bullets.;)

rcmodel
May 29, 2009, 03:11 PM
I have a 16" Colt pencil-barrel carbine that will shoot under an inch with handloads.

A 20" free floated SS barrel should do as well or better.

rc

matrem
May 29, 2009, 10:04 PM
What should one expect?
Perfectly round groups at long distance.
Realistically? No more than one should expect from a good bolt rifle,and even less than from a "bench rest" bolt gun.
The best I've ever been able to consistently achieve with an AR is 1/2moa at 200yds,and that took far more money,work,and experimenting than the few(very few) bolt guns that I've shot,that have equaled or exceeded that.

Maverick223
May 29, 2009, 10:49 PM
What should one expect?I think it should do a bit better than that...who built the barrel? Is the bore good?

SHvar
May 30, 2009, 12:53 AM
Heres my recent results with cheap Barnaul brown bear fired from 100 yards. This was 60 rounds fired in 3 mags, loaded 20 rds each in 4 minutes time total. My DPMS lopro classic groups very good, but then again DPMS are known for accuracy.
Call it 1 minute of camel.
http://i193.photobucket.com/albums/z281/SHvar/Picture021-1.jpg
http://i193.photobucket.com/albums/z281/SHvar/Picture065.jpg

Lovesbeer99
May 30, 2009, 10:14 AM
I have a Bushmaster 20" barrel with 1x9 twist. I free floated the barrel and with a scope and handloads I'm down to 1.5 inch groups consistantly at 100 yards. With milsurp ammo I'm at 2+ inch groups.

You might want to try a few things, but I'd start with the ammo. Try to stay between 52 and 69 grains. Try some Black Hills match ammo or Federal Gold Match.

Before you go crazy though, try this. Drop the bi-pod and get a good sand bag front AND rear rest. Don't rely on your own shoulder for support. See if this helps. If not go to the match ammo, or try handloads.

Good luck and shoot safe.

tkcomer
May 30, 2009, 01:05 PM
This will give ya an idea of what they shoot: http://www.theboxotruth.com/docs/edu8.htm

longdayjake
May 30, 2009, 01:21 PM
I have had less luck with stainless barrels for some reason. They have been more picky for me than other regular and chrome lined barrels. I had a DPMS sweet 16" like the one in the box of truth that I wouldn't trust to shoot past 100 yards. That said my 16" midlength stock barrel from rock river shoots sub moa with my handloads all day long.

hinton03
May 30, 2009, 01:52 PM
I only own one AR, but I did plently of shooting of the M16 in my 23 years of service and I would say you should be able to get 2" 5 shot 100 meter groups from just about any quality base AR. My bushmaster nationall match shoots well under MOA with my pet loads.

When I have an accuracy problem with a rifle the first place I look, after trying several different loads, is the crown. You can have it recrowned for almost nothing, you can even do it yourself by buying a tool from Brownells.

If it still has problems then I get down to the business of bullet seating depth, which is tricky and time consuming. After that if I have not solved the problem the gun goes.

Maverick223
May 30, 2009, 03:19 PM
I have had less luck with stainless barrels for some reason.Me too, and I don't know why. The only SS barrel I want is on a brush gun, simply for maintenance reasons.

SHvar
May 31, 2009, 12:41 AM
Next time I get the chance Ill try some barnaul brown bear in 5 shot groups, and PMC for comparison, then some of my handloads.
Ill fire from a single sandbag, sitting, and Ill bet that theres less difference than what the Box of truth posted.
Anyone who sees that much difference with most plinking rds, etc to handloads at 100 yds is blaming the wrong gremlin for their groups.

FlyinBryan
May 31, 2009, 12:48 AM
lol, without the pic, i would think minute of camel must be a terrible rifle.

sarduy
May 31, 2009, 12:56 AM
just an opinion...

my "new barrel" was shooting about what you are getting with your "new barrel" when the count was around 100 rounds...

i have found a lot better accurary now that it's around 400 rounds shots, it need some brake-in period "300" rounds at lease for me.

since you have a 1/9 twist i would stick to 55gr-62gr bullets no more than that and just shoot at lease 200 rounds more, dont look for accuracy, just blast some rounds at the range, once you get home clean it and on your next trip to the shooting range try for accuracy, remember that cold bore shot are different than the other 2-5 shots after that.

Dobe66
June 1, 2009, 09:52 PM
Thanks for all the input. Kept seeing references to 1:9 twist until it dawned on me that it was my typo error from the get-go. Should have been 1:8.
At any rate, various advice led me down the path of doing a little crown polishing, aggressive bore cleaning and a little bore polishing. Groups dropped in half but still will need to address some flyers and larger groups on the 69gr bullets - better groups means restart on identifying best powder load. Will do some more serious bore and crown "lapping" in the future for even better results.

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