Basic accuracy question about ARs

[ForeverArmed]

I have two basic Bushmaster ARs: one 16" and one 20". Each has a 1/9 twist, is chrome-lined, and has standard (non-freefloating) handguards. Each rifle has maybe 3000 rounds through it due to general plinking -- however, I'm quite nearsighted and only recently started buying optics so I could get into slightly more "serious" target shooting.

With a good 10X scope on each rifle, the best I can manage is a 2" 10-shot group at 100 yards with Federal American Eagle 55gr. A more typical 10-shot group with Spanish 5.56 NATO surplus is 2.5-3" (especially from the carbine). Most of the shots will go into 2", but there will generally be a couple that go out a bit further. This is from a semi-rested position on a bench -- front handguard rested on solid wooden plank, rear buttstock rested on a somewhat-flimsy bag but held as steadily as possible. The greatest source of motion of the sight picture prior to each shot seems to be from my heartbeat!

For comparison, when I shot a friend's .223 bolt rifle with a scope of similar power, I got about a 1" 5-shot group at 100 yards. I know that a 10-shot group will tend to be larger than a 5-shot group, but even allowing for that, it still seems better than what I'm getting with my ARs.

I know that a bolt gun is generally more accurate than a semi-auto, but I'm wondering...do my ARs have unacceptable accuracy? Or is this about standard? Or do I just suck at shooting and need more practice and/or new glasses? Your thoughts are appreciated.

 

[SomeKid]

Well, first off, I must say you are doing better than me.

However, you said this, and I think this may be a factor:

The greatest source of motion of the sight picture prior to each shot seems to be from my heartbeat!

I have heard that the all around legends of target shooting have learned to time their shots with their heartbeats to minimize this problem. You might already know the thing holding back your improving on your own accuracy. Might be something to consider, or this post may be noise. Either way, I wish I had two ARs.

 

[RockyMtnTactical]

Sounds about right to me. Add a new trigger, free floated barrel, SS barrel, etc... and you might be able to cut 1-1 1/4" off of your groups with some 68gr Black Hills OTM.

Chrome lining, that horrid bushy trigger, and the lack of free floating barrel is what is really killing your groups.

Semi Autos are the most innacurate of the various styles of firearms, and for a semi the AR is very accurate.

Are your guns combat weapons or target rifles?

 

[ForeverArmed]

Wow, that was quick. Thanks for the fast replies, guys.

SomeKid: I've heard that as well, and I've also made some attempt to time my shots between heartbeats -- however, it's tough to determine whether I'm succeeding in eliminating that factor.

RockyMtnTactical: So these groups are about right for my setup and ammo? If so, then I'm happy with them, as I bought these weapons more for potential TEOTWAWKI weapons than for target shooting. I guess I'm just a little obsessive about my rifles being at least "par" -- know what I mean?

 

[RockyMtnTactical]

I'd say they are on-par. If they shot much worse than 2MOA or 3MOA than It'd bug me... because AR's should shoot around 2MOA in a stock form.

At any rate, they are plenty accurate enough for TEOTWAWKI.

As long as they are reliable, you should be good to go.

 

[ForeverArmed]

That's good to hear. Yeah, they've been completely reliable as long as decent mags are used. That's a big point in their favor.

Thanks again.

 

[Powderman]

Well, let me kick over the apple cart....

2" from a production AR15 at 100 yards is NOT good. Your rifles are probably capable of doing much better than that.

Here are some things to aid in shooting an accurate group:

1. The idea of using a hard rest is not too good. Get yourself some sandbags--preferably ONE big sand bag.

2. Make sure that your position when shooting is comfortable and correct. If you're shooting from the "free recoil" position (rifle on rest on the bench), build your position carefully.

First, assume a good seated position at the bench. The bench top should be at or about your ribcage for a good position.

Next, place the sandbag on the bench. Check and clear your weapon; now hollow out a good recess in the bags. Set the rifle in it, and position the rifle so that it lays in the sandbags without support. Now, sit at the bench. Lean forward so that your chest lightly touches the bench and so that both elbows can comfortably be placed on the bench.

After this is done, pull or push the sandbags so that the rifle's buttstock is aligned naturally in the pocket of your shoulder when you are seated.

Next, check alignment of the weapon with the target. You should be able to lower your head, look through your sights or scope and be pointing slightly above your point of aim. If not, re-adjust the sandbags until this is so.

Assume a good, steady seated firing position. Place the buttstock in the pocket of your shoulder.

Here's an important part, and one that most shooters from the bench miss--the position of the off hand. Take your off hand, cross it underneath the weapon and place the rear stock swivel in the web of your hand. Use this to pull the buttstock back into the pocket of your shoulder, and to maintain pressure of the stock back into the pocket of your shoulder. Lessen the pressure maintained by the firing hand; ideally, you should be grasping the pistol grip with moderate pressure and NO backward pressure.

The next important part when shooting from the bench WITH a scope is positioning of the face and head. Your cheek should be making firm and steady pressure on the stock. To assume the proper position, place your head so that proper eye relief is obtained. Now, raise your head and make contact with the side of your jaw LIGHTLY on the stock. Without moving your head forward or rearward, move your head straight down while making contact with the stock. You should feel the skin on your face compress upward. Move your head down until it is stopped by the cheekbone.

This is known as the STOCK WELD, and is very important for accurate shooting.

Position your trigger finger properly--right at the pad on the first finger. Now, sight in and concentrate HARD on the juncture of the crosshairs--NOT the target.

Once you have done all of this, snap in. Cock the weapon and dry fire a few times. Make sure that you practice proper breath control--two or three deep breaths will saturate your body with oxygen. Now, take a deep breath, let about half of it out as your rifle settles on target. Stop the exhalation and start steady rearward pressure on the trigger until the hammer falls. Make sure that the crosshairs do not move when that hammer drops.

Now, it's time for live fire. Insert an EMPTY magazine into the weapon and lock the bolt to the rear. Insert one cartridge into the chamber and release the bolt. Re-build your position and shoot. Relax for about one minute, and fire another shot in the same manner. Shoot as many rounds as you wish to form your group; 3 to 5 shots is usually used. If you do everything right, you should see a drastic improvement in your shot group.

I have an Armalite A4 20" upper on my AR; it's also chrome lined, with a 1-9 twist. Shooting my favorite loads (25.0 of Varget under a 52 grain Sierra MatchKing, crimped lightly with a Lee FCD) and with a Simmons 6.5-20x50 scope, I am able to achieve 1/2 to 3/4" groups from the bench at 100 yards.

Good luck, and good shooting!

 

[Lebben-B]

Another thing to think about is your choice of optics. The greater the magnification, the greater the perceived rifle wobble will be. On some of my long range scopes, when I crank up the magnification, every movement regardless of how slight results in noticable scope movement. If it's financially feasable, you might want to think about getting a scope with a lower magnification - say between 4x and 6x.

Mike

 

[Fly320s]

Forever,

Have you tried switchin ammo brands or bullet weights/styles? Different rifles like different ammo.

 

[de]

Foreverarmed, the one thing I always noticed as a swat and tactical instructer was form. But you say you shot a one inch group with a friends rifle. Well, consider that up to 30% of your accuracy can and will fade with a bad trigger. I don't know how many AR15s and M16s I shot in a 20 year career, furthermore how many counter-sniper rifles I shot in training. The one thing that always made the difference was a good trigger.
The first thing a new or used rifle gets at my place is a trigger job. Then we will get an honest evaluation of the rifle's potential. That bushy should shoot under an inch with good ammo, optics, rest, and a good trigger. My M4 bushy will, but it has had a trigger job. Think about it. How was the trigger on your friends rifle in comparision to your ARs trigger?

 

[Quintin Likely]

Lack of a float tube doesn't really matter from a bench, that shows itself most severely when shooting the rifle from position with a sling. The elevenity pound trigger though, will hinder your progress towards good groups.

 

[toecutter]

The basic accuracy of an M-16 (AR-15) shooting XM193 should be under 4" at 100 yards, 2" is considered acceptable. (This is for production line guns the military issues).

Most if not all are capable of more than this, however you need to be using something just a tad better than factory federal XM193... The black hills ammo is really good stuff. I havn't shot any in quite a while (I roll my own) but I could average 1" at 100 yards with NM sights.

Also, free float tubes are designed to take the stress off the barrel when using a sling. They were created because in the prone position, highpower shooters with a tight sling could bend the thin ar-15 lightweight barrels. While I like having a floated fore-end this is not a "must" to get good accuracy out of the AR.

I definately agree with the sentiment that a huge part of the issue is the trigger in most cases. Take it to a gunsmith, and have an idea of how light you want the trigger. Unless you know what you are doing, buy a set of gauges and a stone, there are no other tools needed to do a trigger job (this means no dremels or "power tools") rub it once or twice on the stone, re-assemble and test. If you take too much off you could find yourself in a nasty situation at the range later. And always always perform a function check before putting live rounds in!

 

[Quintin Likely]

I don't think someone should be grinding on an AR15 trigger if they don't know exactly what they're doing. Buying a complete, ready to go trigger would be a lot easier (and if things go really wrong with the grinding, a lot safer) than trying to tweak the original trigger yourself.

Rock River makes a pretty good drop in "match" trigger. Jewell makes one, but it costs more than the RRA. I don't recommend the Bushmaster/CLE trigger, 'cause they get kinda spooky and inconsistent if not cleaned and set up perfectly (and even when perfect, they still aren't all that great). JP Enterprises probably has triggers to suit your needs too. Cost no option, the Geissele trigger is supposed to be the best of the best.

 

[AK103K]

You may be at the mercy and accuracy level of the ammo too. Most military ammo is spec'd at 2-3 MOA, not sure about factory commercial. You might have the best shooting rifle in the world, and it cant do better than the ammo.

I have two 16" Armalite carbines, one a standard (C) model, the other a free floated, match barreled and triggered, (T) model.

The (C) rifle shoots like most any other decent AR. Its got the basic crappy AR trigger, a 4 MOA Aimpoint with BUIS, and with good ammo fired from prone,(using iron sights) 2" is about the best you will get, and 3" is probably more the average.

The (T) is a whole different critter, with my reloads, using Nosler BT's and Sierra's "match load" of 4895, it will shoot them all into one tiny little hole at 100 yards, prone off a bipod, if I do my part. The ammo issue becomes apparent here when you switch loads. This same rifle, will only shoot Lake City GI ball into 2" at 100 yards, all things being the same but the ammo.

If you reload, you can tailor the ammo to your gun for the type of shooting you want to do. If you dont, you have to try them all until you find one your gun likes. You may or may not luck out.

Dont assume a big scope will make you a better shot. A good shooter with iron sights will often shoot better than an average shooter with a scope. My favorite scope for the AR, and most rifles, is a 1.5x5 Leupold. The lower power scopes are a lot more versatile.

Also dont think a bench will make you a better shooter either. It also wont teach you anything but how to shoot off a bench. Your a lot better off to learn to shoot from field positions.

 

[MechAg94]

2" groups with normal ammo or surplus is pretty good. That is mostly the ammo I shoot. I have a little Black Hills ammo, but I haven't tried to shoot it up yet. Reloads or match ammo should make a difference all else equal.

I can generally do 2" to 3" with my Armalite with iron sights with surplus or standard military ammo. I can do better sometimes.

I do agree that you don't need a big scope. Too much magnification can be a distraction. I agree that 5X or 6X is more than enough for 100 yards. Iron sights are my preferred though scopes can help sometimes.

What Powderman said should also be learned. I don't use sand bags, but rather a sand bag rest I have, but it is still a good read.

 

[DogBonz]

Get your self a good trigger

And listen to powderman.

When I put a Jewel triger in my AR, my groups were cut almost in half. The stock triggers in ARs are horrible, They cause you to put so much force on the trigger, that often times the result is that you move the rifle as you pull the trigger, or when it breaks.

 

[Powderman]

If you wish, you can also order a complete lower with a match type trigger built in. I agree wholeheartedly with the other posters; the trigger can make a LOT of difference.

I have fired AR's with different triggers; the absolute best I have felt was the Jewell; next was the Armalite match trigger group, and third--believe it or not--is the Williams set trigger from Oly Arms. Unset, it breaks clean right at about 3 pounds. Set weight is measured in ounces. It is an absolute dream to shoot.

I would also recommend that you learn the fundamentals of iron sights, too. When you put everything together, the proper steady hold factors--stock position, stock/cheek weld, finger position, sight picture, sight alignment, support and breathing--a good AR15 can be downright scary accurate. I managed--from the prone, locked in with a good, tight military sling--to shoot an extremely tight group--right around the size of a quarter--rapid fire, 20 rounds downrange at 100 yards. Get those fundamentals down!!

 

[jem375]

My ar's don't shoot Federal American Eagle very good also...XM193 is more accurate and will be my SHTF ammo...

 

[DMK]

With a good 10X scope on each rifle, the best I can manage is a 2" 10-shot group at 100 yards with Federal American Eagle 55gr.

While not bad ammo by any means, that certainly isn't the most consistent ammo out there. I'll bet you could reduce that group with some match ammo. Try a couple brands and weights until you find the one your rifle likes. Guns can be finicky beasts when it comes to absolute accuracy.

I'd be very happy with the results you're seeing.

 

[browningguy]

Federal American Eagle 55gr...Spanish 5.56 NATO surplus

With the ammo he is shooting those groups are quite decent. Try some of the Black Hills reloads in anything from 50 gr. - 69 gr. and watch them tighten up.

 

[ForeverArmed]

Wow, people here are really helpful. Thanks to everyone for the replies -- there's a lot of valuable collective wisdom here.

Powderman: Thanks for that great overview of the basics. While I've been attempting to do many of those things, I can certainly use more practice. And you bring up some points that are new to me -- in particular, the part about applying no backward pressure with the pistol grip (I've been applying some rearward pressure). I'll try doing that and some other things your way and see how it goes. One counterpoint I'd like to respectfully make, however, is that 3 or 5 shot groups are generally going to be smaller than 10-shot groups. Believe it or not, I read in a book on ballistics somewhere that the extreme spread of a 10-shot group is statistically equivalent to the ES of a 5-shot group divided by 0.812. So, say, a 2" 10-shot group is really like a 1.624" 5-shot group. I'm not sure which size group people are generally referring to when they talk about MOA, etc. I do believe military testing is done using 10-shot groups, however.

The trigger issue seems to be something a lot of people agree on, and I'm not surprised. Yes, the triggers on my ARs do suck. That bolt gun I shot had an excellent trigger.

As for the ammo, so far I've only tried the aforementioned Spanish NATO surplus and Fed AE, as well as Winchester Q3131A. The Fed AE seems to give the best results. While I'm by no means an expert at shooting and am certainly introducing at least some inaccuracy, the point about ammo that's only spec'd at 2-3 MOA is well-taken. Clearly I can't do better than the ammo. Maybe I'll spend some cash on some match stuff. Handloading would be ideal, as I'm aware that it can give the best results, but unfortunately I have neither the time nor the equipment right now.

What people said about the 10X scope being too much is very interesting. Fortunately I didn't buy the 10X specifically for AR shooting (I'm looking into buying a new bolt gun at some point) -- I was just trying to use it to test accuracy. Maybe I'll get something smaller or just get new glasses and stick to the irons. (I really have become a bit more nearsighted since I got my current glasses and do need a new prescription.)

Thanks again, folks!!

 

[Don't Tread On Me]

For an AR-15 (M4, M16A4) to leave the factory at Colt or FN, it must be able to shoot under 4moa @ 100 yards. I believe they shoot a magazine using 3-round bursts from a vise style rest.

However, AR's are capable of much better. Usually in the 1-2" range with a plain-jane chrome lined 5.56 chamber service barrel. Having a 5.56 chamber is more detrimental to accuracy than chrome lining is in my opinion. Match barrels like Kreiger have significantly tighter specs than service style barrels. Actually, the Krieger has a tighter throat and leade than some bolt action rifles!!

55gr American Eagle is a far cry from being a match-grade ammunition. Out of that 1/9 Bushmaster, the 69gr Sierra Match King will shrink groups quite a bit. The other option, would be the 60gr Hornady VMAX, which is hailed by many 1/9 barrel owners to be extremely accurate. Either one of these choices will drop group size quite a bit I am sure.

I was on AR15.com when I came across a post by a fellow called "Molon" which had pictures of groups fired from a 1/7, 5.56, chrome lined, Govt profile barrel. One 10-shot group was free floated barrel, optics, 75gr match ammo - the other was not free floated. Free floated results were 1.2" @ 100 yards. The non FF'd was 1.9" @ 100 yards. Remember, both with match ammo.

I tried this myself, using my own handloaded 75gr ammo. I free floated my 1/7, govt profile, 5.56 chrome lined barrel and I got 1.3" @ 100 yards. I didn't try non-free floated, but I'd guess my results would probably be similar. Even if a little worse, still not a big concern.

I am very happy that my results match the results of someone else. Always a good sign. Some might scoff at that accuracy, but I consider that to be extremely excellent accuracy. Tack-driver accuracy for a service style military pattern autoloader. So the AR is capable of the best accuracy of the military rifles (for the price).


It is all about perspective. If you're getting 2moa with American Eagle, non free floated - you're doing GREAT. 2moa is far better than any military standard for accuracy in that style rifle. Don't get sucked into all the internet-exaggerations and lies about accuracy. The internet can have you believe that if you're not shooting 0.25moa groups with your standard barrel, that you're a freak. What you're shooting is good.

With 2 moa, the worst shot possible is 1" off the point of aim. If a center of mass is say 10", divide that by 2" and you could probably go out 500yards with that accuracy and that ammo and have a high probability and confidence that if your aim is correct (and drop/windage is right) that the accuracy of the rifle will give you a hit.


If you want to shoot for groups, the #1 thing you can do is free float that barrel. Absolute biggest improvement you can make. For $53, the DPMS one is supurb. It floats with good clearance, and installs with a standard GI wrench. If you want fancier or rails, price goes up.

The #2 thing is to get a better trigger. For $90 if you shop around, you can find the RRA 2-stage. This significantly improves the trigger which eliminates a lot of the tension and wobble from trying to cleanly break an 9lb AR trigger. I've shot 1.4-1.6moa groups using a standard AR trigger, but it was a PAINFUL process trying to get a good clean pull with all that weight. A good trigger makes it easier, and in the long run - more accurate.

#3 would be to use some type of match grade ammo. If you handload, great. If not, you could try Federal Gold Medal 69gr SMK, there's the Hornady 60gr VMAX, and there are a variety of loads from Black Hills which is universally held as very accurately loaded ammunition.

It's possible that you can get down under 1" with these factors, even with a 5.56 chrome lined barrel. If a govt profile can do 1.2", there's a good chance a 1/9 hbar will do better. If you're looking for just good all-around accuracy or combat accuracy - you already got it.


Good luck.

 

[Nail Shooter]

I have a 1 in 9 twist, 20" chrome lined HBAR Bushy. The LARGEST 5 shot group it has ever shot from a bagged rest is 1 5/8" (OPEN sights @ 100yds) once I figured out what the rifle liked. I brought the group size down significantly by loading my own ammo--my gun likes the Sierra or Hornady 52 gr BTHP match bullets, AND installing the RRA match trigger group. As others have said, the stock trigger is not that good for precision target work, it's just too heavy.

If yours has a carry handle, and you're using the adapter to mount the scope, that can also be contributory to poorer than expected accuracy. IMO, a flat top upper configuration is the only way to go if running a scope. Regards,

NS

 

[10-Ring]

Last summer, a shooting buddy & I build our 1st AR's - his a Stag & mine an RRA. We sighted them in at 100 yards and before we left the range we started a little competition. We put 3/4" orange dots on our respective targets, loaded our CA legal, 10 round mags and started...most hits on the dots, loser bought lunch.
Both of us put most of our shots into the dot relatively easily, total group size of about an inch
We both used Eotech sights
I had a bi pod mounted, my buddy was using sand bags
We were both shooting Federal ammo
Both are 16" barreled guns, his is chrome lined, mine is a std RRA barrel

Short story long, you should be able to do better than 2" groups Relatively easily

 

[AK103K]

This is only 5 shots, but the first three are the three in the center. The flyer was me. My buddy always says, "never look at your groups until your done", he's right.

100 yards. Prone off bi pod. Nosler 55 grain BT's over 25.1 grains of 4895 (Sierra's accuracy load, right out of the book).

This is the rifle, 16" Armalite M15A4 (T), Leupold 1.5x5 on an ARMS lever mount.