How to Understand Accuracy Results

[South Pender]

I often read posts on this forum to see the level of accuracy obtained by others shooting the same cartridges I am--more or less to determine whether I'm doing as well accuracy-wise as I should be with these cartridges. However, accuracy results are often hard to use. For me, the NRA American Rifleman standard of reporting an average group size of 5 consecutive 5-shot groups at 100 yards is close to a gold standard insofar as really-valid information is concerned (although I guess an average of 10 consecutive 5-shot groups would be better), and that's how I record my own accuracy data for future reference. I might add that recording my own data this way generally leads to poorer results than most of those I read about!

Often, however, shooters will describe a rifle as a half-minute gun or as shooting in the 2s and 3s. Or it shoots in the 4s. But what do these reported results mean? Are they based on some averaging of group-size results? Are they the best groups shot with the rifle? Are groups cherry-picked in some way--say with the worst groups thrown out? I realize that reporting 200-, 300-, and longer-range results is also useful information, but it is how the results (at whatever range) are characterized that is the problem.

Not knowing exactly the meaning of reported group sizes makes evaluating one's own results difficult. What do you all think? Is it reasonable to ask shooters to report aggregated results?

 

[CharlieNC]

Of course the distance is also a major variable. But to me group size at 100yd is not interesting; I appreciate it is to many. And "accuracy" should include hitting the bulls eye. The simplest way to grade accuracy and precision is scoring something like a fclass target for 20 shots. But that is why we have different shooting disciplines.

 

[Fast14riot]

In my opinion, 100-200 yard groups show the precision of the gun, 600-1000 yard groups show the precision of the shooter and gun.

On this forum, I'm reasonably confident when most say their gun is a .25moa or other, gun, that's a reasonable average.

Personally, I have a gun that will shoot in the 1s, but I'm not capable of doing that over an extended time and amount of groups, I can stay inside the 9 ring at 1000y pretty well, though. Its a matter of what you choose to compare to.

 

[Idaho-Lefty]

The .2's stands for a group diameter, Center to Center ( farthest out, Holes of group ) of,.. .200 to .299 thousands of, an inch. The 3's = .300 to .399 dia ( ctr to ctr ). Measurement @ 100 yards.
I like to do, my, Bullet / Load, "testing" at 200 and 300 yards, as sometimes "problems" show up at, Distance that aren't present at, 100 yards.

 

[South Pender]

The .2's stands for a group diameter, Center to Center ( farthest out, Holes of group ) of,.. .200 to .299 thousands of, an inch. The 3's = .300 to .399 dia ( ctr to ctr ). Measurement @ 100 yards.
I like to do, my, Bullet / Load, "testing" at 200 and 300 yards, as sometimes "problems" show up at, Distance that aren't present at, 100 yards.

Yes, I understand what .2s, etc. means--i.e., I understand how the measurement is made. What I'm not sure of is whether it means an aggregate (and if so, how many groups are included), just the best single group, just the best few groups, etc., when shooters report such results.

 

[Idaho-Lefty]

I measure the Outside of the Bullet Holes in the Group with, Calipers then, subtract, the size of the Caliber used. As I'm mostly, a Hunter, Plinker and INFORMAL Target Shooter, I don't bother measuring / keeping, ALL my Groups / Targets, as I sometimes I'll "pull one" a 1/4 " out, to screw up, the group. Usually, I keep track of, ( hold on to ) 3 or 4 good "Wallet" groups for, EACH Rifle's Loads, to put in, my Load Book's, Log for, future references.
Formal Target shooters, USE Agg's ( Many groups at,.. an AVERAGE of all, groups ).
Your first paragraph, pretty much, defines, the "Gold Standard" ! Doubt if, most "Informal" Target shooters shoot THAT many Targets at, a sitting ! Personally, I'm NOT into wearing my barrel out, too quickly !
2 or 3 groups then, home to "adjust" load / bullet depth, etc. Normally, I shoot, 2 or 3 Rifles to keep the bbls Cool. Could I put together 5 Targets with, 5 Shots each, in a Target at, ONE sitting, in the .2's ??,..
NOPE !

 

[K22]

I'm primarily a precision varmint and predator hunting which means I strive for 1/2 moa precision at 100 yards give or take. I use 100 yards as a comparative standard for load development since hopefully the human error is minimized at this distance and I can get a clearer idea which rifles / loads work for my purpose.

Not all my varmint rifles that qualify for hunting can achieve this level of precision on a consistent basis but are fairly close varying upwards from 5/8 to 3/4". Case in point, I have a Rem Model 7 which is one of my light weight stalking rifles meaning I use for walking around and taking shots under 250 yards. It's about a 5/8" to 3/4" rifle yet in 2019, I had a 98% success rate with this rifle in the field.

I do have a few rifles with heavy varmint custom barrels that shoot fairly consistent 1/2 moa groups if I do my part which I don't always do. In other words, in my case, the biggest variable is me when it comes to shooting.

Furthermore, I'm not a good bench shooter since I spend most of my range time shooting as practice for field shooting which means I'm shooting off a shooting stick. After I get a load that I'm reasonably satisfied with I spend very little time on the bench if any with that rifle and load. I do keep detailed records on my range practice and field performance and try to learn from it.

With regards to reloading, I take a middle of the road approach meaning I endeavor to produce precise reloads employing a number of advanced reloading procedures but don't go to the extent that some of my bench shooter friends go to where their goal is the smallest possible group. These guys turn necks, anneal, and use bushings to achieve optimum and consistent neck tension and from what I've witness, these procedures work but my requirements are not as stringent as theirs and I don't want to spend the time and money chasing .1's" group tightening. If I can drop and ground hog or coyote out to 300 yards on a routine basis shooting off a shooting cross stick then I'm satisfied since that meets about 95% of my shoot opportunities where I hunt.

The bottom line is it comes down to your personal requirements for your rifles and reloads. In other words how much precision do you need. In the final analysis, for most of us this is a hobby not our profession. A hobby is suppose to be fun and enjoyable. What will it take for you to enjoy shooting?

 

[PatMiles]

Interesting reading, 3 parts.

How To Predict The Future – Statistics For Shooters Part 1

I actually believe the average shooter might get more value from this Statistics for Shooters serie...

precisionrifleblog.com

Muzzle Velocity Stats – Statistics for Shooters Part 2

Consistent muzzle velocity is key for long-range shooting, otherwise, bullets that leave the muzzle...

precisionrifleblog.com

Precision & Group Size – Statistics for Shooters Part 3

This article is going to dive into the most effective ways to quantify the precision of a rifle and...

precisionrifleblog.com

 

[JEFFPPC]

The more multi shot groups making you feel good, the less left to be competitive with. Just my way of thinking.

 

[ronsatspokane]

Interesting reading, 3 parts.

How To Predict The Future – Statistics For Shooters Part 1

I actually believe the average shooter might get more value from this Statistics for Shooters serie...

precisionrifleblog.com

Muzzle Velocity Stats – Statistics for Shooters Part 2

Consistent muzzle velocity is key for long-range shooting, otherwise, bullets that leave the muzzle...

precisionrifleblog.com

Precision & Group Size – Statistics for Shooters Part 3

This article is going to dive into the most effective ways to quantify the precision of a rifle and...

precisionrifleblog.com

Very good articles.

 

[jelenko]

On this forum, I'm reasonably confident when most say their gun is a .25moa or other, gun, that's a reasonable average.

This is my perception also.
Unless someone specifically states that they've done X number of Y shot groups, I think it means the statement above. [I'm sure there are some who quote their best ever 3 shot group and ignore the ones that weren't]

I am like K22 - except I compete in 'across the course'. For my needs, I'm done with load development when several 5 shot groups over a couple days are .5 to .6 MOA. I have found that the group size doesn't change a lot - with the vast majority at/slightly below .5 to .6 to .75 MOA. I'm sure if all the shots I take were grouped into 5 shot groups, some would be an MOA or more.

Personally, I wouldn't chase what 'should be' unless that is what you enjoy. And, if so, 'could be' is probably a better goal. I like to chase what I need to do the job at hand.

 

[jackieschmidt]

Relating to the precision and accuracy of a given combination depends on the Discipline you are participating in.
In 100/200 yard Group Competition, the magic number is sub .200 agging capability. That means you can shoot five 5-shot groups, each on the 7 minute time period, and the average measurement of the five groups will be less than .200. We call that a “teen agg”.
In 100/200 Score Shooting, you are shooting at five individual 1/2 inch bulls eyes with a 1/16 dot in the center, which is the X. As you might guess, we are not shooting to hit that 1/2 inch bulls eye. We are aiming at that X. You shoot 5 bulls eyes in a 7 minute time period. you do this five times, for a total of 25. The bulls eye is a 10. So a perfect agg in score shooting will be a 250 25X. The standard of excellence is to consistantly hit 20+ X’s on a given day.
All shooting Disciplines have evolved to where it takes a very specialized rifle/caliber/ cartridge combination to be competitive. A 1000 yard rifle will not be very competitive at 100/200 yards, and a rifle designed to compete at 100/200 will not be competitive at 600+ yards.

 

[JEFFPPC]

As a broad statement Jackie is correct. However, when trying to compare disciplines(SEEMS TO INTEREST IN THAT LATELY) one of the small 6 mm cartridges commonly used at 1000 if tuned for100, might often be competitive at the shorter distances used by a shooter with those skills. A normal short range cartridge will not be competitive ar 1000 yds irregardless of who is the shooter. I shoot a lot of 500 yd matches and win with a 6 PPC.....won't work at a 1000.

 

[JEFFPPC]

As an aside to this conversation since the shooting season is shot for this year ,here is a story for you. Some years ago in my area, offhand 100 yard rifle shooting was very popular. No slings,no butt hooks,no palm rests. Lot's of 700 Varmint rifle used . A group of archers at the one club stated they could clean our clocks at 25 and 50 yds. So we shot 5 rifle shooters vs 5 archers. Everyone shot 5 shots at each of the 2 distances. It was ugly The Indians have never recovered. Rule of thumb, right tool for a given job. They have never asked for a rematch.Yeah, off subject a bit but facing long winters is tough.

 

[Shooter13]

As an aside to this conversation since the shooting season is shot for this year ,here is a story for you. Some years ago in my area, offhand 100 yard rifle shooting was very popular. No slings,no butt hooks,no palm rests. Lot's of 700 Varmint rifle used . A group of archers at the one club stated they could clean our clocks at 25 and 50 yds. So we shot 5 rifle shooters vs 5 archers. Everyone shot 5 shots at each of the 2 distances. It was ugly The Indians have never recovered. Rule of thumb, right tool for a given job. They have never asked for a rematch.Yeah, off subject a bit but facing long winters is tough.

That would have had to been the dumbest bet in the world! I've shot a lot of archery, never, not once did I think I could outshoot my gun at that range!

 

[davidjoe]

The more multi shot groups making you feel good, the less left to be competitive with. Just my way of thinking.

Right on. Someone who truly shoots a lot will know very soon, with very few shots, where a particular rifle stands. Close range like 100/200 with a fully supported rifle minimizes wind and holding variables. It won’t assure you though that the twist is ideal for long range, (if it’s marginal) or how your bullet handles wind. But if groups are tiny close in, that does confirm that the rifle is accurate.

Long range testing only, can also be misleading because it’s possible to be blown “in” fortuitously, or pull a shot into a group by chance (such that a flyer gets hidden) just like it’s possible to throw a perfectly performing bullet out. But this is where shooting a lot helps. You know from other guns or barrels what is reasonable to expect, and when you see good results for conditions you are familiar with, there’s really no mistaking it. Multiple 10 shot test groups mentioned above add up to a match in barrel life and bullets, and I’d rather have that knowledge come in a match.

 

[dragman]

That would have had to been the dumbest bet in the world! I've shot a lot of archery, never, not once did I think I could outshoot my gun at that range!

Depends on the archer. 50 yards and in I have know archers that will outshoot ANY one free standing. But then again i do know some world class archers.

 

[INTJ]

As a broad statement Jackie is correct. However, when trying to compare disciplines(SEEMS TO INTEREST IN THAT LATELY) one of the small 6 mm cartridges commonly used at 1000 if tuned for100, might often be competitive at the shorter distances used by a shooter with those skills. A normal short range cartridge will not be competitive ar 1000 yds irregardless of who is the shooter. I shoot a lot of 500 yd matches and win with a 6 PPC.....won't work at a 1000.

I agree with both you and Jackie. I have to do most of my tuning at 200 yds for my LR BR rifles that are shot at 600 and 1000 yds during matches. Especially with the 6 BRA, I need five-shot groups at 200 yds that are 3/8" or better. Occasionally I'll get a 1/4" group at 200. That of course is using long range bullets, and that is a lot closer to what dedicated SR BR rifles do at 200 that what LR BR rifles used to do.

At 300 yds I think the advantage may now be with an LR BR rig over a SR BR rig. It would be a fun match to find out!

 

[JEFFPPC]

Depends on the archer. 50 yards and in I have know archers that will outshoot ANY one free standing. But then again i do know some world class archers.

Yeah, these guys thought the same thing. The archers shot silver dollars at 50 yrs. The rifle shooters shot dimes.

 

[INTJ]

Depends on the archer. 50 yards and in I have know archers that will outshoot ANY one free standing. But then again i do know some world class archers.

Contests such as this have been going on for a very long time. I remember 40+ years ago a very accomplished local archer challenged some handgun shooters to a 50 yd match. The archer lost pretty badly.

I have no doubt that an accomplished archer could beat a casual firearm shooter at 50 yds. But when both are equally accomplished, the archer will lose most of the time.