AR-15 Accuracy

[gpr]

I am left wondering how to increase the accuracy out of an AR-15... I just got done building an AR-15 with a Stag 6HL upper. (it is the lefty version). When you buy the complete gun Stag grantees 1/2 MOA, so i figured their upper on my existing lower would still produce good results as i have seen great reviews on them. However it is shooting terrible groups.

I had the barrel threaded for my suppressor from mile high shooting, then I faced the upper receiver and installed the barrel with green lock tight around the barrel extension to make it tight. It is a 24" SS bull barrel with 1:8 twist and adjustable gas block, and houge hand guard. The lower i installed a Luth stock, JP silent capture spring, Jard 1.5lbs trigger.

I went to break in the barrel this weekend and dial in the scope. I am shooting maybe 2-3 moa with cheap 55gr PMC. Granted it isn't match ammo but I can throw this ammo in any other gun or AR and shoot much better groups. I only have shot about 100 rounds, if i shoot more will the barrel break in and shoot any better?

I'm wondering what to do? I read the build thread on getting 1/2 MOA AR, and was will go check the gas tube installation. Other than that i have no idea why this thing doesn't shoot better. I have never seen an AR shoot as good as my factory Remington 700 223,..... was hopping to accomplish that with this build.

I will try some match grade ammo here soon. Do you think 1:8 twist is too much for a 55gr bullet? I typically shoot and hunt with 53gr hornady v-max superformance ammo as i love the speed from this ammo, plus have great luck with very good accuracy and high BC (for a 223 bullet).

 

[JoeBUtah]

Please forgive me if this is the obvious, but have you checked the torque on all the mounting screws for your scope? That ammo might be a problem, but you should get better than 2-3 moa. Try some better ammo; maybe something a little heavier too. I just put a 1:8 Faxom on a build and breaking it it I got easy 1moa with 55 gr reloads of mine. Sometimes you just gotta work to find the right combination for the rifle.

 

[SRPowah]

While you should see better from that ammo, run some quality heavier ammo through it. Maybe the barrel simply hates that round, as we can't easily explain the nuances of these rifles sometimes. Push another 50-100 rounds down the tube and you could see it tighten up.

 

[bigjake83]

It's kind of hard to give you accurate answer to your questions because the fact that you've kind of monkey fucked with the upper opens the door to more possibilities ..IE did you properly lap your upper receiver?? Have you properly installed you're gas system?? Did you under or over or Torque your barrel nut?? Did Mile High accidentally fuck up your rifles crown or improperly thread the muzzle?? And yes without a doubt pick up some Black Hills 69 and 77 grain match ammunition you don't need the new stuff the blue box remanufactured will work just fine.

What trigger are you running..??

Just FYI I had a Stag M6 and it loved the 75gr Hornady Superformace..

 

[MarkCO]

Ugh. Really hard to diagnose accuracy issues on-line, and you have some good suggestions so far. Locktite in barrel extensions is pretty much worthless unless you also use an activator and facing receivers is something reserved for crappy ones, which Stag is not. Mile High has a good rep, but there could be a chip or something in the crown or termination of the rifling due to the threading.

I have seen the buffer tune change groups, barrel torque, shims, all kinds of things. In some cases, I have merely taken an upper apart and put it back together and cut groups in half.

But, if you can not get to 1MOA with some match grade ammo, there is likely one or more things you can do to get there.

 

[Mile High Shooting]

1/8 twist barrel, Try some Black Hills or Fed GM in the 69-77 grain ammo.

Concentrate on staying in the rifle, ie, follow through

Should be shooting sub MOA

If you have any questions on the crown, etc, bring it by and we'll take a look, but we are pretty picky about what goes out the door.....

 

[OH58DViper]

Shocked that PMC didn't give you accurate groups, I mean that stuff is essentially FGMM.....Joking of course, I'm sure she will shoot better with some match ammo. 1/2 Minute in a gasser is a tough, but I wouldn't even worry about it until you shoot some quality ammo though it.

 

[Ghogs Nightmare]

I havent shot their 223 version but if its anything like the 308/7.62 offering that PMC ammo shoots MOB consistently (minute of barn that is). As long as your scope is mounted properly concentrate on your technique with good ammo you should see a definite improvement.

 

[Tonsofguns]

you're shooting 2-3 inch groups with plinking ammo out of an ar 15 and surprised with the results? If you want to win bodybuilding competitions, it's not just about the lifting, you got to eat well. Try a handful of different types of match ammunition, and report back. Also, just because your rifle can shoot half inch groups, does not mean you can shoot half inch groups, especially out of a gasser.

 

[quicklx]

I have 16" AR that will hold 3/4 MOA or better all the way out to 400 yards with 75 grain hornady HPBT and TAC. It will do very close to the same with factory hornady 75gr superformance or TAP ammo. However.....if I put 55gr ANYTHING or 62gr ammo it is a turd. Groups open up to 2" at 100 yards.

This particular rifle is nothing special at all. Aero upper and lower. BCM BCG, BCM gas block, spikes (FN) hammer forged barrel, JP comp, spikes ST2 buffer, and a Wilson combat TTU trigger. Assemble by myself with aeroshell grease and properly torqued barrel nut.

Your rifle sounds to be of a better pedigree than the one I mentioned. So as others have mentioned, if your torque on the barrel but is good and the scope isn't loose I would try some better ammo.

 

[Greg Langelius *]

My Stag Model 6 shoots Prvi-Partizan 69gr and 75gr Match well enough to meet the 1/2MOA guarantee at 100yd. Weaver V-24 Classic mounted to the flattop with Weaver 1" See-Thru Rings. No frills.

Handload: Win Brass, no prep, 24.4gr Varget, HDY 75gr HPBT Match at 2.255" OAL, CCI BR-4.

I'd suggest the likeliest cause for the inaccuracy is the crown. It would be polite to give the last firm that worked on the muzzle an opportunity to inspect and correct the crown if needed.

The 1:8" twist should not be a problem with 55gr projectiles, but they still need to be put together with more care than 55FMJ typically receives.

Greg

 

[spaniel]

I hear "1/2 MOA guarantee", but you are shooting cheap factory loads, not even good ones, much less reloading?

It's pretty good to get an AR consistently under 1/2 MOA with reloads built for the rifle. Even good "match ammo" may or may not be liked by that particular rifle. The gun should do better than 2-3 MOA, but until you try good ammo you haven't tried anything at all.

 

[Harleyreb1]

I'd try better Ammo and report back

 

[Mike_in_FL]

I will sound like a broken record but, I would use a good copper remover and clean the bore well before I tried again. I had the same experience, cleaned all the copper out and started again with much better results. I guess if you're lucky and have a really good barrel without much to polish in the throat your rifle will shoot right off the bat. But my luck is never that good, lol.

 

[sheepdog697]

Id start with match ammo. Just like most have said. If you continue to have bad groups with the ammo, you can eliminate that variable. I had an ar with jp rifle and bolt, it shot around 1.5" with the 55gr plinker ammo. If i put good,not even great, ammo through it i would see under 1" easily. If that doesnt work Start with the easiest things to check before you start tearing apart your gun.

 

[gpr]

I'm pretty sure nothing is wrong with the crown or the threads. Mile High did an outstanding job and had a great turn around.

I have tried different ammo, and while group size is smaller it ain't no 1/2 MOA gun. 1 MOA is the smallest group i could get.

I tried HSM 55gr V-max, Hornady 55gr V-max, and Hornady 75gr BTHP Superformance (only ammo I could source locally). Oddly enough the HSM shot the best at around 1 MOA group even though it had the worse SD. The match Hornady ammo was amazingly consistent and had an SD of only 6 fps, which i find that hard to believe if i didn't see it myself. Surprising that the most consistent velocity ammo did not shoot as well at 1 1/4 MOA, then the horandy v-max 55gr was around 1.5 moa.

I would of thought the gun should shoot better than it does with the 1/2 moa guarantee. I will be trying some hand loads to see how they perform, but as far as AR's go this one is probably my favorite yet (it shoots really nice and is awesome to not have gas and brass ejected into my face).

 

[delfuego]

Complete upper? Is the bolt headspaced? Or is the bolt aftermarket or Stag?

 

[Regulatori]

Do you have a lot of past experience with precision AR shooting? I had experience with half inch bolt guns but found AR's sometimes have kind of a learning curve to get the most accuracy. It took me many range visits to really get comfortable behind one.

See if you can get your hands on some Black Hills 77gr OTM. My 1:7.7 barrel is very accurate with any of the major MK262 brands: Magtech, Black Hills, IMI, etc..
It also might be worth while to see if you can stretch out the range and don't get so hung up on 100yds. Maybe spend a day hitting steel plates at various distances and just have a day of "fun" shooting, not shooting where you're going in expecting specific group sizes. Sometimes a few days of that and then going back to shoot some groups can do wonder. I feel a lot of shooting is mental....almost as if you go into the range with the thought "my gun better shoot 1/2" it sets you up for failure because you're putting too much pressure on yourself.

Maybe I missed it but what are you using as a rest? Sandbags, bipod? See if you can get the rifle solid in some bags where you're able to lift your head off the scope and when looking back in, the rifle is still dead nuts on the center. With your trigger you should be able to have minimum contact with the rifle to fire.

You sound like you know what you're doing so this is probably just preaching to the choir.

Some barrels are just damn finicky. My 16" Bartlein will do .50" groups with good ammo but then instantly go to 2" with lower end stuff. I always joke that it's a snooty barrel.

 

[gpr]

Thank you for the help and suggestions. And yes i bought the complete upper from stag, so the barrel should be head spaced from them. However i have not checked it. Also I have shot AR’s a lot before but never had a super accurate one to try and shoot tight groups. I’m not stating I’m the best shooter out there, but when I squeeze the trigger and I see the bullet hole appear where the cross hairs were never close to then I’m pretty certain it isn’t my shooting.

I did some shooting this weekend. I am not sure why but the barrel didn't like the 75gr Hornady ammo I have and is consistently shooting 1.25 MOA. I’m not sure if it is the barrel breaking in more, or the fact I installed JP tension pins but it is now shooting much better. Trying several different loads and some hand loads I can get .75 MOA consistently, but have never gotten it better than that. So I’m happy with the results as it shot 5 different types of ammo all around .75 MOA.

 

[RTH1800]

I have not seen that many "1/2 MOA" AR's. I have a few that shoot that well or a bit better than 1/2 MOA. One was a stag. I would say the % of off the rack 1/2 MOA AR rifles is not as high as I read about. Quite a few decent quality ones I see do the MOA hover and shoot 10 shot groups from 1-2" at 100 yards. The fast twist barrels seem to shoot heavy, boattail bullets a bit better a long range than short. Not sure why that is.

 

[elfster1234]

I am left wondering how to increase the accuracy out of an AR-15... I just got done building an AR-15 with a Stag 6HL upper. (it is the lefty version). When you buy the complete gun Stag grantees 1/2 MOA, so i figured their upper on my existing lower would still produce good results as i have seen great reviews on them. However it is shooting terrible groups.

I had the barrel threaded for my suppressor from mile high shooting, then I faced the upper receiver and installed the barrel with green lock tight around the barrel extension to make it tight. It is a 24" SS bull barrel with 1:8 twist and adjustable gas block, and houge hand guard. The lower i installed a Luth stock, JP silent capture spring, Jard 1.5lbs trigger.

I went to break in the barrel this weekend and dial in the scope. I am shooting maybe 2-3 moa with cheap 55gr PMC. Granted it isn't match ammo but I can throw this ammo in any other gun or AR and shoot much better groups. I only have shot about 100 rounds, if i shoot more will the barrel break in and shoot any better?

I'm wondering what to do? I read the build thread on getting 1/2 MOA AR, and was will go check the gas tube installation. Other than that i have no idea why this thing doesn't shoot better. I have never seen an AR shoot as good as my factory Remington 700 223,..... was hopping to accomplish that with this build.

I will try some match grade ammo here soon. Do you think 1:8 twist is too much for a 55gr bullet? I typically shoot and hunt with 53gr hornady v-max superformance ammo as i love the speed from this ammo, plus have great luck with very good accuracy and high BC (for a 223 bullet).

soooo dont take this the wrong way, but the only way you're going to get consistent 1/2 moa accuracy out of ANY AR is doing your own reloads.... ammo ammo ammo, and some good load development,,,,, and learning how that particular AR likes to be shot... heavy hold, light hold and letting the bags do the work, load bipod, dont load bipod... most times ive found if you load the bipod, and bring half of the rifles weight back into your shoulder as a heavy hold & use a good bipod with a good rear sand bag = will produce good consistent sub moa groups... and even still to produce consistent 1/2 moa groups with any AR, when ever you pull the trigger, is kinda BS..

 

[Conaso]

I agree with Gunny, ammo is the key. If it's commercial ammo, then you'll just have to find the brand that works best. I have a Stag Mdl-6 and only used some bulk reload to get the Vortex PST 6-24x scope on the mark. I then worked up my reloads - 53SMK (23.0gr H322), 69SMK(25gr. Varget), and 77TMK (23.6gr Varget). Typically, .5 - .75" at 100, easily. Working on the COAL on the 77TMK to fine tune (2.30-2.36") using backcavity-modified PRI magazine. But I also have a PRS stock and Geiselle DMR trigger.

 

[MElank]

Reading for the past couple of years two names come to mind. Elfster and Padom are an excellent source of information regarding semi-auto shooting and hand loading accuracy.

 

[Tonsofguns]

Again try many types of ammo brands and weight. In my experience honardy tap is accurate enough, but by no means match Ammo. Try some black hills 77 grain, also try some lighter loads as well. Another great ammo company is prime, they have a 55gr match.

lasltly, again to shoot at your rifles potential is difficult, especially with a gas gun, with all the moving parts. I put tens of thousands of rounds downrange annually, and it's rare that I can shoot at any of my rifles potential.

Few tips for shooting. Make sure you have consistent pressure on grip everytime, follow through on your shots, load the bipod, practice dry firing a lot, and don't put too much pressure on the cheek weld.


QUOTE=gpr;n6308578]Thank you for the help and suggestions. And yes i bought the complete upper from stag, so the barrel should be head spaced from them. However i have not checked it. Also I have shot AR’s a lot before but never had a super accurate one to try and shoot tight groups. I’m not stating I’m the best shooter out there, but when I squeeze the trigger and I see the bullet hole appear where the cross hairs were never close to then I’m pretty certain it isn’t my shooting.

I did some shooting this weekend. I am not sure why but the barrel didn't like the 75gr Hornady ammo I have and is consistently shooting 1.25 MOA. I’m not sure if it is the barrel breaking in more, or the fact I installed JP tension pins but it is now shooting much better. Trying several different loads and some hand loads I can get .75 MOA consistently, but have never gotten it better than that. So I’m happy with the results as it shot 5 different types of ammo all around .75 MOA.
[/QUOTE]

 

[gpr]

. and even still to produce consistent 1/2 moa groups with any AR, when ever you pull the trigger, is kinda BS..

I'm starting to believe this and that AR's simply aren't as accurate as bolt guns. Really my goal with the gun is to get an accurate varmint hunting gun. If it shoots around 3/4 MOA I'm happy.

However when i first got the gun and started shooting it, and the groups were 2-3" in size that is definitely not acceptable. Now that it is shooting better, I'm satisfied. I don't have much free time so I would rather spend my time out shooting 1000 rounds of factory ammo at 1 MOA then spend the time reloading and shooting 200 hand loads at 1/2 MOA.

Now if i could just find someone that makes a left hand AR-10 upper so I could build a 6.5cm.......

 

[Conaso]

Now if i could just find someone that makes a left hand AR-10 upper so I could build a 6.5cm.......

If anyone will do it is Stag Arms; but they would have to see a market demand for them, considering they just came out with their Model 10.