Home Forums Hunting & Shooting AR and Tactical Rifles most accurate ar barrel

Ummm, OK.

Mean radius is a better measure of consistency than extreme spread, but you have to do a little work to get it.

If you want to "punish" outliers more, calculate the root mean square radius.

I report accuracy from an accumulation of groups. For hunting rifles its generally 3 shot groups but a passle of them. Day in and day out.

Rarely shoot 5 shots in a hunting situation.

The reason I shoot 10 shot groups in the AR, after the ladder and initial 3-5 shot groups confirm, is thats the main use of the AR to us for years is CMP competition, 10 shot rapid fire groups.

Plus when shooting 10-22 shots for score/group it allows me to better see if my groups have shape to them, or flukes... if you know what I mean. I"ll take a rounded out group almost every time over one that has 5-6 in a knot and 3-4 fliers.

Of course most all my AR testing for competition was done at 300 and 600 yards.

Testing at 600 I shot 5 shot groups to test neck tension, primers etc....

But when I had time at matches I would compare the best 2 ammo combos in 11 shot strings one right after the other and do that a lot before you really know whats best.

And it was a dang good way to learn exactly how disastrous switching powders can be to grouping for a few shots until things settle back in.

Because three shots mean absolutely nothing. Worse than that, 3 shot groups have just as much a chance of leading one to a wrong conclusion as it does a correct one. Even multiple 3 shot groups mean nothing unless they are shot on the exact same target and the aggregate of all shots is tallied. As well I do not believe in "fliers" or make excuses for bad grouping. Since starting to work somewhere that mandates 10 round groups for just about everything.... Strangely- I no longer get "fliers".


If one can not shoot 10 rounds rested without flinching, "pulling" a shot or "throwing" a shot they have no idea what their gun is doing, and strongly need to stop talking about accuracy and learn to shoot.

EVERY rifle I use is grouped for 10 rounds. From M4's to MK13's. 6.5 lb M7's to 18lb match guns. And not just once but repeatedly. I strongly believe in grouping every time I shoot. It checks consistency, reinforces fundamentals, validates your zero, and reveals possible gun/scope issues.

Having tested it numerous times, there is little to no difference between one or two 10 round groups (from even flyweight hunting rifles) and three 5 shot groups or five 3 shot groups when shot one the exact same target. 10 rounds will show exactly what that rifle/ammo/scope combo can be expected to do on any given shot.

For a hunting rifle, a target with ten 1 shot groups from a cold bore would tell me a lot more about what to expect from my rifle than one 10 shot group.

On the other hand, ten 1 shot groups from a match rifle would leave out a lot of information.

Can't argue with that. Neither would the COL.

Because one you start pulling the trigger on an AR, you don't want to stop, and an AR doesn't cost 2 bucks a round like some factory hunting ammo.

Ok for curiosity for anyone running 10 shot groups, do you allow the barrel to cool? I know on the match .243 I shot 10 shots in a rapid manner to confirm nothing was weird because 10-15 shots in a 2-3 minute time frame was somewhat typical for a match and I was running a Heavy plama contour. What does a ten shot group look like for a pencil barreled AR?

There is that.

I do not let the barrel cool. For those that think that ten 1 shot "groups" is more applicable to hunting rifles- having tested it several times, it will result in the same grouping. Unless the gun is jacked up. Then you might get better groups with the shoot once, ten times thing. Of course shooting ten round groups will show you if there is something mechanically wrong with the system, and that's a good thing.



With good ammo 10 round groups prone mag monopoded with good chrome-lined barrels go sub 2 MOA.


This is my current work gun- a Colt Block II M4.

First group of the day shot right handed-





Second group shot left handed-




Left handed group was obvious NPA problems. Been quite a while since I have worked left hand for accuracy. Keep on mind both were shoot prone , no rest.

Now most will say "gee that sucks" "my rifle will do sub-MOA all day long...... As long as I do my part" or other such nonsense. Funny because if I can't guarantee my part than I have no freaking clue what the gun will consistently do, and then I'm just bs'ing everyone including myself. Interestingly I never get to see all those "sub-MOA all day long" guns on the range which is ironic seeing how I spend A LOT of time on ranges and see A LOT of guns shot, both military and public.

I shoot 3 shot groups on my pencil barrel AR cause its chrome lined and not a target gun. It'll do 1.5 or so MOA whether at 100 or at 400 and it generally hits what I aim at. Which brings up the important part, killing what you need to kill in spite of it not being a 1/4 MOA gun.

My mountain rifles though I shoot 5 as well as my Noveske light weight. That's good enough for me.

I'm confused. Are you saying that a hunting rifle will put cold bore shots into a ragged hole or it's "all jacked up"? I couldn't tell from the way I read it.

Quick reply used....meant for Formidilibiousocity.

And I've actually gotten legitimate answers this time. I don't agree with the necessity FOR MOST FOLKS APPLICATION, but I at least got better answers than "zombies".

Not an AR, but has to do with groups.


I could show probably a dozen 3 and 5 round groups in the .2 to .3 inch range from a 308 I have. Thing is, it ain't a .2 inch gun. Not even close. When multiple 3 round groups are over laid onto one another it magically turns into a 1 to 1.2 MOA gun. The irony is that if I just shoot 10 round groups I get the same thing....












No cherry picked groups, covered up bullet holes, or "holes in the target from another gun". I believe that is every 10 round that gun has shot in the last year save two. And both of those were right at 1 MOA as well.




To address something that was mentioned earlier and is always thrown out there- there is no such thing as a "cold bore shift" or "cold bore shot" unless the barrel is crap. There is such a thing as a cold shooter though.

I'm not trying to be argumentative, I think maybe I'm not following what you're saying and am trying to understand.

So a barrel is crap unless every shot from a cold bore goes to the same spot and every hot bore shot goes to that same spot?

And how big does that spot have to be before the barrel is "crap"?

And if the barrel has to shoot to the same spot regardless of how hot it is, why stop at 10? Why not 30 round groups?

You seem like a guy who shoots a lot, I'm just trying to follow what you're saying.

Ross Seyfried's standard was always cold bore shot followed by a second fast follow up shot, on a 3in paster, at 200yd, in FEB, then again in APR, then again in JUN...... or "that rifle don't hunt".

So I'll first answer your questions and then post the why.

Yes, a barrel is crap unless every shot goes to the same spot. How could it not be? If you are trying to hit a target, ie deer, rounds that group really close together but not in the center are useless.


As for the size spot it depends. For my big game rifles 1.5 MOA 10 round groups at 100 yards is about the limit. That's my general rule because every normal deer clambering is capable of killing deer out to around 600 yards. For the LR specific guns I want 1 MOA max for 10 rounds. Work M4's with match ammo I replace the barrel when it hits 2 MOA for 10. That's day in and day out.


As to why not thirty rounds? Because I've tested it. A lot. Statistically 10 round groups will show where something like 98% of all rounds fired will land. 20 and 30 round groups just send more ammo through the same hole in the target.



What I'm saying is that what is termed "cold bore shift" or the "cold bore shot" impacting differently than the follow on shots, isn't because the bore is "cold". Neither is "walking" as the barrel gets hot. Now if there is residual stress with the barrel/action/bedding or something else mechanically wrong with the gun, then yes you could see that. But given a properly built barrel and gun, any shift you see from cold bore or "Walking" from firing more than ______ amount of rounds, is from cold shooter (not getting NPA, press, etc) or the natural dispersion of rounds.

Personally I don�t shoot �groups� much , I am way more interested in hits.

The first shot in any group, 10 or 5 or 3, is a freebie. At the first shot all groups are equal. Conversely, for me and how I use a rifle or carbine the first shot is the most important.

One other point to consider is that the more accurate your AR is the fewer number of shots would be required to show the max dispersion, at least at the resolution we are used to when talking normal ARs.

In other words if we had an AR that legitimately put all shots through the same hole then a 1 shot group and a 10 shot group would be the same size, a single bullet hole. If your AR legitimately is a 10 MOA gun then you will need to fire quite a few bullets to fill out the entire dispersion and get repeatable accurate data.

I think 10 shots is a better indication of the shooter than the AR, as putting together a good 10 shot string is way more than twice as hard as a good 5 shot string which is more than twice as difficult as a good 3 shot string.

3 Shots, at point of aim, is a good indication that the gun is shooting, 5 shots, at point of aim, is pretty much a sure thing that the gun is shooting.

As I don�t shoot competitions that require 10 shot groups and my real world uses for the AR have nothing to do with 10 shot groups I rarely practice shooting 10 shot groups. Of more importance to me are 1 to 5 round strings on a specific sized target, measured as hits or misses. For me this is more productive and a better use of time and ammo.

Here is a 3 shot string,@ 100yds, on point of aim, within the adjustments of the sight.



5 shot string (@ 100 yds) on point of aim showing some shooter error.



5 Shot string (@ 100yds) with shooter induced flyers. (and a fly that landed on the target)

John, that's a nice look rig, and some nice looking groups.

Would you mind sharing some details?