Size Matters (group size, that is)


PDA






Jordan
August 24, 2003, 02:57 PM
I'm wondering:
when a magazine review states a rifle will shoot, say, 3/4 moa, or your buddy asks you how your rifle shoots and you tell him 1 moa, or you buy a high-end precision rifle and it is "guaranteed" to shoot 1/2"... is that stating the BEST YOU WILL EVER SEE OUT OF IT? Or is that what you can count on as a CONSISTANT AVERAGE (figuring the right ammo, no wind, etc, etc)?

The reason I'm asking, I've been putting a lot of money into an accurate rifle lately and I can't say it will shoot 1/2moa consistantly. I can't say it will shoot 5 rounds into 3/4" consistantly.
I generally come back from the range with a few targets with tight little 1/2 clover leafs. And several more that are more like an inch!

Then I open up "Hunting" magazine and see the latest RemChester review boasting the author's 5/8" groups using some sloppy hunting ammo! Did he shoot ALL DAY to get that lucky group? Or am I just unlucky that none of my production rifles will shoot ANYTHING like that?

So what gives! I've certainly put as much care (read: money) into building it as the "guaranteed" 1/2 inch guns(McMillan, Robar, etc). And while they're stipulating factory "match" ammo to achieve this, I'm using carefully constructed, tuned to my rifle, taking all the extra steps, handloads!

What are the established rules for stating the accuracy of a given rifle? Have I misunderstood them and am now persuing a totally unreasonable goal of a RELIABLE 1/2-3/4? If someone tells me their FAL shoots sub-moa, it that like saying they caught a fish that was "T H I S" big!?

If you enjoyed reading about "Size Matters (group size, that is)" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
swifter
August 24, 2003, 05:09 PM
Most folks hang on the occasional wonderful group as tho their rifle shot it all the time:rolleyes: . Hogwash.
Show me an aggregate of five groups, five rounds each. This is what you & your rifle will shoot consistently. And even that will have good & bad days!

My Remmy .222 shot an.015" group... I keep it in the target notebook for that rifle...It is the best group that rifle, and/or I ever shot:evil: .It sure will not do it consistently, or even repeat it...:banghead:

Mostly, gunrag groups are the best that rifle could do, and if you are getting .75MOA from a factory gun consistently, you're on the right path.

Accuracy is the result of a process , not a couple tricks or "secrets"...:what:

Good shooting,

Tom

Futo Inu
August 24, 2003, 05:21 PM
"What are the established rules for stating the accuracy of a given rifle?" I don't think there are any; hence the confusion. The manufacturers COULD mean, when stating a particular group size capability, that:

A. YOU should be able to consistently shoot said groups with factory ammo
B. YOU should be able to consisently shoot said groups with precision hand-loaded ammo, tuned to the gun.
C. An EXPERT should be able to consistently shoot said groups with precision ammo, tuned to the gun.
D. An EXPERT will get one group such as this after shooting 10-20 groups, with precision ammo, tuned to the gun.
E. Only the rifle locked into a ransom rest where it cannot move, and the trigger mechanically, precisely fired with precision ammo, tuned to the gun, will result in a group like this (and maybe after a few tries as well).

Several other combinations before, after, and in between, obviously. In pistols, it seems like what they mean is "E" when speaking of wonder-1911 guaranteed 1/2" at 50 yards or whatever. With rifles, I'm not sure, but given my experience with sales puffery, I'd imagine that at least SOME claimaint/manufacturers mean "E", whereas some with more integrity might mean B, C, or D. I doubt very many mean A.

AK103K
August 24, 2003, 05:23 PM
Your chasing a demon that you will never catch, although you may come close. While I guess "groups" are the accepted norm for a rifles worthiness, I think a group of targets, made up of single, "cold shots", that impact within that magical size limit from the aiming point would be a more accurate way to judge the rifle. After all, its the first shot that counts, right? Then again, this all goes out the window in a gopher hunt now dont it? :)

tex_n_cal
August 24, 2003, 05:47 PM
well, these are three consecutive 5 shot groups, and the rifle that shot them:evil:

http://www.thehighroad.org/attachment.php?s=&postid=76221

Art Eatman
August 24, 2003, 06:30 PM
I've noticed that many of the gunzines give the average group size for several strings, when they talk of what a rifle will do.

Basically, I've always figured that you can throw out the occasional bad group, and don't count the truly once-in-a-while exceptional group when you talk about what a rifle does. (Ya gotta save that exceptional group to brag about, though. :) )

I have had the occasional rifle that would always put the first shot into the same point of impact, even though I couldn't get really tight groups from it.

Purely opinion, but I don't think shooting more than three shots for a group for a hunting rifle is important. Target competition is a whole 'nother deal, entirely; five-shot or even ten-shot strings are important, there.

Art

sanchezero
August 24, 2003, 06:32 PM
I'm with ya Jordan.

I'm pretty new to the 'precision' rifle thing. I guess I avg 3/4MOA from the bench with my only LRR. Of course, this includes the occasional 1.5" group that I seem to shoot as well as the best I've shot at 3/8".

I'll be psyched if I can go 100 rnds without exceeding 3/4MOA.

Jordan
August 25, 2003, 01:21 AM
There's some good responses here. Thanks.

I was a little discouraged about shooting this morning when I wrote that, but now, fresh back from the range, am singing a whole new tune! Got some SWEET results even out to 600yds! To be honest, I've never shot at that distance before and it was a great confidence builder. Got the same MOA groups out to that distance (<2" @ 400, <3" @ 600, etc) which was really encouraging! Flyers were few and far between too, and probably due to an intermittant breeze in most cases.

I agree that the cumulation of cold shots is a more valuable tool than groups for measuring real world effectiveness of a rifle. I shoot at the thick, construction paper targets but I have thought that it would be handy to have targets that you could overlay on each other and shine light through to compare "groups" of cold shots.

Thanks again, guys!

Maddogkiller
August 25, 2003, 03:52 AM
(<2" @ 400, <3" @ 600, etc)

Wouldn't these numbers indicate 1/2 MOA?

Swampy
August 25, 2003, 07:56 AM
Art wrote:

Purely opinion, but I don't think shooting more than three shots for a group for a hunting rifle is important. Target competition is a whole 'nother deal, entirely; five-shot or even ten-shot strings are important, there.


AMEN !!!!!

I can see good logic for using 3 shot groups and the "cold shot" to determine the usefulness of a hunting arm.... but I get my funny bone tickled when I see guys trying to tell me that their DCM legal AR-15 they just bought is a 1/2 MOA gun when all they shoot for practice is 3 shot groups...... just like they did with their Winchester '94 before deer season....... or that their "new" CMP M1 will shoot 1 MOA cloverleafs (3 shots)... but that's only occasionally, and if you discount the two flyers at 2 and 6 O-clock.

When I first started Highpower a few years back I started working up loads with 5 shot groups, just like I always did before. Didn't take me long to discover that some of those fine looking loads at 5 rounds showed a whole different face on the target when you increased the number of holes. :)

I learned quickly that 8-10 shots gave a much more meaningful indication of how that rifle and load combo would do during a match.......

If a rifle is prone to throwing flyers, 3 shot groups won't always show that. It may only throw a flyer every 5 or 8 rounds. Shooting 8-10 shots each group almost guarantees that if a rifle has a problem with flyers, you'll see it on the paper.... then you can make a determination of the problem and fix it.

8-10 shots also increases the chance that the SHOOTERS little flaws will show up on the paper. They can also then be ID'd, addressed, and rectified.

Here lies the crux of the issue for Competition shooters. The rifle does not act alone. It is a "team effort" between the rifle, the ammo, and the "nut holding the butt". What shows up on the paper is a combination of the "weak factors" of all three of the major components. Larger groups just make it easier to find and fix them.

Best to all,
Swampy

bogie
August 25, 2003, 12:18 PM
Let me guess - you have NO IDEA what the wind was doing between you and the targets...

And I'll bet that on one of the days, the wind was more consistent...

Get a half dozen wind indicators (a stick and surveyor tape will work) and plant 'em between your bench and the target. Then look at 'em occasionally... You'll soon be able to see just how much environmental conditions screw up your life when you're trying to shoot a small group.

Jordan
August 25, 2003, 12:20 PM
MDK: Yep, 1/2" out to 600! I was thrilled. Still, I can't say every target I shot at 600 was as good (though they all were an HONEST sub-moa) and as such, I don't feel I can call this a 1/2 MOA rifle... though I'm sure a gun manufacturer or gunzine would... it's a Capitalist/Consumerist plot to make us all unsatisfied with our rifles so we run out and buy theirs!

Good points, Swampy. Again, I think overlaying targets of 3-5rnd groups would be telling. Personally, if I shoot much more than 5 rnds at the same paper it turns into a soup sandwich... feel like I'm just banging away and lose my concentration, lose track of spread trends, etc.
Since it sounds like you have a fair amount of experience could you tell me some of the things you've trouble shot with flyers? What are some of the causes you've determined, how have you addressed them etc.?

Bogie: You're absodamnedlutely right... I felt no wind where I was shooting.. but down range a few hundred yards, it was moving things around pretty good! It's in my log book as something I blew it on and something to watch closer in the future! I'd hate to use the indicators much beyond an occaisional training aid... Don't want to turn into a BR weenie.

bogie
September 29, 2003, 06:12 PM
Just thought of something...

Tony Boyer (he's the fellow in the funny looking hat with all the match pins on it in the Leupold ads...) says that three shots prove that a rifle shoots.

Five shots proves that the person pulling the trigger can shoot.

And five groups confirms it.

Dr.Rob
September 29, 2003, 07:42 PM
What is steel to the hand that wields it?

You know zeroing your rifle off the bench without a rest (even sandbagged) does take a lot of patience and practice. I KNOW my Savage 116 will shoot 3 shot 1/2 inch groups (after three I let it cool off). This has little to do with how anyone ELSE will shoot my rifle in the field or off the bench.

I have an old Savage rifle that will still shoot 3/4 inch 100 yard groups, even though the stock is gouged, the barrel scratched and the bluing worn thin. It doesn't look like much, but it works.

Found out that after years of being convinced my Marlin 336 would NOT shoot better than 3-4 inch groups at 100 yards that years later, it will suddenly shoot 1.5 inch groups.

I also know that I'm a better 'snap' shooter than my partner Bryan, but that Bryan is more patient and can shoot a lot farther and more accurately than me.

Guess that makes me a "spotter" instead of a sniper.

Ed
September 30, 2003, 10:11 AM
According to statitistics yes you should throw out the high and low groups and go with the mean or median or whatever it is called. So out of 10 groups maybe throw out the best and worst. Where does the correct number of shots per group come from? I see lots of people use 3 lots use 8. if I shoot and can hit a quarter sized target consistantly with no "flyers with 3 shot groups,over and over, and I'm not saying that I can, isn't that the same as 6 or 8 shot groups on the same target? I ask because most of my rifles won't hold 8 rounds. And again, is 8 enough? I'm asking because I honestly want to know. I could care less what someone calls 1MOA. I'm just concerned with putting the bullet where I want it to go.
I really don't believe that in finding your personal "MOA" with a rifle you can throw out "flyers". If it happens on paper it can happen when you need the rifle to hit the target anytime, so that should be included in how you shoot with the rifle.

Futo Inu
September 30, 2003, 11:33 AM
"I learned quickly that 8-10 shots gave a much more meaningful indication of how that rifle and load combo would do during a match"

That's good information to know, Swampy - I'll think I'll start using 8- or 10-shot groups instead of 5 for everyday testing.

Also, it's nice to know that those damned rifles will throw out occasional flyers - I had always blamed all flyers on my errors - whew, that's a relief (actually, I'm only half kidding there).

Edward429451
September 30, 2003, 11:49 AM
I've been sticking to 10 shot groups for awhile now. Used to throw out the best and worst to get the mean but lately I'm saving the best & worst. The best shows what is possible and if I've done it before, I should be able to do it again or even better it. The worst really shows what you can expect if you're having a bad day. Its easy to extrapolate your average looking at a good & bad together, and its also easy to say...I can expect this on a good day and at least this if I'm having a bad day.

uglygun
September 30, 2003, 01:14 PM
Over the past 5 years I've adjusted the way I shoot for groups.

When I first got my rifle and began to shoot for groups I would do the 3 shot group stuff, quite often I'd get groups that were bording right about 1/2 inch for 3 shots but every so often I'd get an unexpected 1 inch 3 shot group. I didn't know for sure if it was me, the ammo, or the rifle. About the same time as I got my rifle I took a statistics class at the local jr. college and was introduced to the concept of sample size and the importance it plays in demonstrating a normal distribution.

After that class I started shooting 5 shot groups to get a bit larger sample size, here I found that I was shooting closer to 3/4 inch groups on average with my better ammo. It was a much closer approximation of what my rifle could deliver or what I could expect to shoot. Still though, I'd get the odd 1 inch group from time to time.

Now, I pretty much do 10 shot groups and usually it will be 2 or 3 groups inorder to get an idea of what's going on with my rifle. My rifle is generally used for varmint shooting and at times it can be pretty fast paced where 3-5 shots could be fired in a fairly small amount of time depending on the size of the field and it's population. Many of my 10 shot groups are fired about as quickly as I can pull the trigger after the crosshairs settle back on target, no waiting for the barrel to cool. So far my best load for the rifle is doing 3/4 inch on average for multiple 10 shot groups which I consider pretty darned decent. Looking at those groups, often times 6-7 shots will be inside of 1/2 inch and then the remaining 3-4 are responsible for opening it up to 3/4 inch.

I haven't given much attention to trying to get a load that will average 1/2 inch or less, having roughly 60% of my loads being capable of that level of accuracy at 100 yards is good enough for me.

What I need to start working on next is developing loads that are consistent enough for 3/4MOA at 400 yards and beyond, loads that have good velocity with little deviation or extreme spread.


About 6 months ago I picked up a 300WinMag PSS which I'm gonna develop loads for as I learn to shoot it accurately(big difference coming from an accurized 15 pound AR15). My first loads being tested on paper at 500 yards are hovering right around MOA but I'm definitely the weak link in the equation, way too shakey right now to wring enough performance from the rifle to know if my loads are improving.



If I was hunting larger game or atleast going after something bigger than a tennis ball, the search for a rifle/load combination capable of delivering sub-MOA on a consistent basis would probably not be so important. 3 shot groups would definitely give me an indication on whether a load was good enough for a shot into the vitals on a deer from anywhere from 100-400 yards with most modern high velocity rounds. But for my little squirrels, if I have any hope to nail them at 400+ in atleast a somewhat predictable way I've gotta see what's going on and the 10 shot groups typically will reflect that better than a 3 shot group or even the average of a couple 3 shot groups(to weed out possible barrel heating issues).

Art Eatman
September 30, 2003, 05:04 PM
uglygun, it seems to me that varmint hunters--particularly the prairie dog group--are more akin to competition target shooters than to deer hunters. So, five- and/or ten-shot groups give a much better picture of many-shot accuracy when there will be long strings of shots in relatively short periods of time.

Since it's rare that a deer hunter needs--or gets--more than his first aimed shot, the three-shot group seems adequate, to me. More importantly, the point of impact of the first shot from a cold barrel pretty much MUST be the same, all the time.

Different uses, different needs...

:), Art

ReadyontheRight
September 30, 2003, 06:07 PM
tex_n_cal -- What kind of rifle is that?

If you enjoyed reading about "Size Matters (group size, that is)" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!