5 shot groups "kinda worthless"?

To some folks a one shot “group” is good enough, for others three shots, some use “best three out of five”, others ten shots, etc.

I personally like ten shots, but sometimes five will do. There is nothing scientific about those numbers, it is just my personal preference, YMMV.

Stay safe.

I kind of like the philosophy of how 9Hole Reviews do 9 shot groups. Apparent that tells you more than what a 3 shot or 5 shot group can do. Maybe make more sense if you have the ammo on hand or cheap ammo.

There’s a lot of videos from Hornady and Ultimate Reloader about the fact that people that don’t fire enough rounds to make conclusions with statistical significance. Falls in line with what Jack O Connor said many hunters “think they are crack rifle shots because they generally kill a deer every season.”

The statistics of group size are a bit of a challenge.

With all "special causes" removed (shooter flinch, barrel rub, etc.) so that only normal random variation is present, a single five-shot group will tell you the rifle's long term average group size within plus or minus about 50%. So if the rifle will produce a 1" long term average, five-shot groups between 1/2" and 1 1/2" will routinely happen with no change whatever in shooter skill, ammunition, etc.

The average of three five-shot groups will get you the long term average within about plus or minus 25%.

The number of groups goes up exponentially from there if you want a more precise estimate, so the average of three five-shot groups is kind of a workable middle ground.

Lots of evaluation being done on various ladders of three shots.

What are you after?
First shot hit on a heffalump?
Aggregate of multiple 5 and 10 shot groups at benchrest?
Score for 10-20 shots on target requiring centered hits?

Cityevader said:

Mathmatically speaking, 5 shot groups are "random"

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Yes, as 5 shot group is subset of 10 shot group. And 10 shot group is subset of 50 shot group. Etc. Etc.

Cityevader said:

if say, one brand of ammo is consistantly tight-grouped after 5, and another ammo is consistantly all over the place after 5 then duh, obvious...but if different ammos are sorta kinda similar, then 1000's of hits need to be averaged to determine grouping

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Yes. And after shooting over 30,000 rounds of 22LR, to include a larger "sample size", I embarked on 10,000+ round "Real World" comparison range test capturing 5/10 shot groups at 50/100 yards to monitor group size trend with new 10/22 and T/CR22 during break-in and accurized with parts replacement - https://www.thehighroad.org/index.php?threads/real-world-accurizing-22lr-on-the-cheap.898035/

So after 10,000+ round sample size, I can post the following group size listing from smallest to largest based on average composite of group size trend monitored (And stay tuned, I got 10+ additional brands/weight/lots to conduct 1 year follow up testing) - https://www.thehighroad.org/index.p...t-shipped-pricing.902560/page-5#post-12304852

1. CCI Standard Velocity 40 gr LRN (New) - Boxed (Around 1/2")
2. CCI Standard Velocity 40 gr LRN (Old) - Boxed - Consistent group size (Around 1/2" - 3/4")
3. CCI Blazer 40 gr LRN - Boxed - Consistent group size (Around 1/2" - 3/4")
4. Norma Tac-22 40 gr LRN - Boxed - Based on initial testing 1/2"-3/4" groups (Testing to continue)
5. Aguila 40 gr LRN (Eley Prime) - Boxed - Consistent group size (No longer produced)
6. Aguila 40 gr LRN (Aguila Prime, New) - Boxed - Consistent group size (Larger than 1/2" to 3/4")
7. Aguila 40 gr LRN (Aguila Prime, Old) - Boxed - Consistent group size (Larger than 1/2" to 3/4")
8. Aguila 40 gr CPRN (Eley Prime) - Boxed - Consistent group size (No longer produced)
9. Aguila 40 gr CPRN (Aguila Prime) - Boxed - Consistent group size (3/4"-1")
10. Aguila 40 gr LRN Pistol Match - Boxed, Consistent group size around (3/4"-1")
11. Aguila 40 gr CPRN - 250 round Loose Bulk - Based on initial testing sub 1" to 1.25"
12. Aguila 38 gr CPRN - 250 round Loose Bulk - Based on initial testing around 1"
13. Federal Auto Match 40 gr LRN - Loose Bulk - Group size varied
14. Aguila 38 gr CPHP - Boxes - Group size varied
15. Federal Game Shok 40 gr CPRN - Boxed - Fairly consistent group size
16. Federal Field Pack 38 gr CPHP - Loose Bulk - Group size varied
17. Remington Golden Bullet 36 gr CPHP - Loose Bulk - Fairly consistent group size
18. Remington Thunderbolt 40 gr LRN - Loose Bulk - Small to large groups with flyers
19. Armscor 36 gr CPHP - Boxed - Varying group size with flyers
20. Federal Champion 40 gr LRN - Boxed - Group size varied
21. Federal Value 36 gr CPHP 525 Blue Box (Old) - Loose Bulk - Group size varied
22. Federal Value 36 gr CPHP 525 Blue Box (New) - Loose Bulk - Group size varied
23. Federal Value 36 gr CPHP 550 Walmart Red Box (Old) - Loose Bulk - Group size varied
24. Federal Value 36 gr CPHP 550 Walmart Red Box (New) - Loose Bulk - Group size varied
    
25. Winchester XPert 36 gr LRN 500 - Loose Bulk - Group size varied
26. Winchester 36 gr CPHP 555 - Loose Bulk - Group size varied
27. Winchester M22 40 gr CPRN 500 - Loose Bulk - Group size varied with flyers

It depends on whether you are trying to determine the accuracy of the load, the rifle, or the shooter. I can get a pretty good idea of how accurate the load is with 3 shots. Five tells me a little more about the rifle and more than 5 tells me more about the shooter.

One target regardless of 3, 5, or 10 shots doesn't tell me much. I usually shoot 5 shots with 22's, 223, or other less expensive ammo. But even with my handloads I'm looking at $1 a shot for most of my centerfires. At that price a series of 3 shot groups tells me what I need to know.

Anyone can get lucky and put together ONE good group of even 10 shots, or just have a bad day and shoot poorly. I'm more interested in how consistent my 3 shot groups are over multiple range trips. Ten strings of 3 shots over weeks or months tell me more than 3 strings of 10 shots all done the same day.

As a hunter I'm not going to fire more than 3 shots at a game animal. When you get into longer strings you start having trouble concentrating for that long and you have to deal with barrels heating up. None of which will be a factor for me hunting.

Something I've never done, but a suggestion I read about on a shooting forum was to place a target at 100 yards. Fire ONE shot at the target, only one, and the 1st shot of the day from a cold barrel with no warm-up shots. Then take that target down, save it and repeat that the next range visit. After 5-10 range visits you'll have 5-10 shots on one target. As a hunter that will tell you what you need to know.

jmr40 said:

As a hunter I'm not going to fire more than 3 shots at a game animal. When you get into longer strings you start having trouble concentrating for that long and you have to deal with barrels heating up

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Very good point as group size tends to get larger as barrel heats up.

For the "Real World" threads, full transparency of cold barrel groups were captured along with warm/hot barrel groups as typical range sessions shot 300-600+ rounds, pertinent for high round count plinkers.

And to expand full transparency, round counts for barrels and triggers were included for each range test along with trigger pull weights.

Riomouse911 said:

To some folks a one shot “group” is good enough

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Not exactly the same thing, but on more than one occasion I’ve taken a hunting rifle and put a single round down range just to make sure it hit where it was supposed to.

Otherwise, generally I’m a five shot guy.

jmr40 said:

Something I've never done, but a suggestion I read about on a shooting forum was to place a target at 100 yards. Fire ONE shot.

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A SWATter I know had a clean cold zero for the one shot he was likely to get, but he plotted successive shots as the barrel warmed and fouled, just in case.

ETA: I think that guy is a bit cracked on his statistical mathematics and I am far from a strong statistician but I know enough to feel pretty sure he's wrong.

Shot and measured correctly two 5-shot groups can give you the same data as one 10 shot groups. I would rather shoot ten 5-shot groups than five 10-shot groups. There is that balance between the shooters ability to focus on shooting the group and getting a larger enough group to have meaningful mathematical/statistical significance. Personally I like three consecutive 5-shot groups. The average of that seems to give me a good confidence in what I can expect from that combination of gun/ammo/sights and fitment to me. More is always better but three 5-shot groups makes me feed good, and rarely leads me astray.

I believe in 5 shot groups. And I've shot a lot of them. When working up a load I'll take the best 5 shot groups and shoot a few more to prove them.

I feel that the first shot out of a cold clean barrel tells you more of what you need to know for a hunting rifle than groups although I like for my hunting rifles to make decent groups.

But I'm not a math major!

mcb said:

ETA: I think that guys a bit cracked on his statistical mathematics and I am far from a strong statistician but I know enough to feel pretty sure he wrong.

Shot and measured correctly two 5-shot groups can give you the same data as one 10 shot groups. I would rather shoot ten 5-shot groups than five 10-shot groups. There is that balance between the shooters ability to focus on shooting the group and getting a larger enough group to have meaningful mathematical/statistical significance. Personally I like three consecutive 5-shot groups. The average of that seems to give me a good confidence in what I can expect from that combination of gun/ammo/sights and fitment to me. More is always better but three 5-shot groups makes me feed good, and rarely leads me astray.

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There is a statistical subtlety about 5 and 10 shot groups that doesn't often get mentioned.

If you want to capture 100% of the information about variation, you take the standard deviation. We don't normally do that in the field, because it takes too long.

A five-shot group has 90% of the information content of the standard deviation of that same group. So mentally give it a score of .9 x 5 = 4.5.

A 10 shot group has only 60% of the information content of the standard deviation of that same group. So mentally give that a score of .6 x 10 = 6.

The last 5 shots of a 10 shot group do add information, but not as much as the first 5 when using group size as your scale.

So as strange as it sounds, you are better off averaging two five-shot groups than you are shooting a single 10 shot group.

jmr40 said:

Something I've never done, but a suggestion I read about on a shooting forum was to place a target at 100 yards. Fire ONE shot at the target, only one, and the 1st shot of the day from a cold barrel with no warm-up shots. Then take that target down, save it and repeat that the next range visit. After 5-10 range visits you'll have 5-10 shots on one target. As a hunter that will tell you what you need to know.

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That's how I finalize my loads for my 280 Rem deer rifle loads. All I really care about is the 1st shot.

I believe in just cold bore shot placement, 3 shot, 5 shot, and up and up. “Kinda useless” depends on what you are wanting to know.

denton said:

If you want to capture 100% of the information about variation, you take the standard deviation.

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The problem is, people are usually unwilling to go out the multiples of the standard deviation necessary to include a large majority of the values.

If you are shooting at a target for group or score, nobody is figuring the standard deviation, all shots count, even the widest of the extreme spread.

jmr40 said:

It depends on whether you are trying to determine the accuracy of the load, the rifle, or the shooter. I can get a pretty good idea of how accurate the load is with 3 shots. Five tells me a little more about the rifle and more than 5 tells me more about the shooter.

One target regardless of 3, 5, or 10 shots doesn't tell me much. I usually shoot 5 shots with 22's, 223, or other less expensive ammo. But even with my handloads I'm looking at $1 a shot for most of my centerfires. At that price a series of 3 shot groups tells me what I need to know.

Anyone can get lucky and put together ONE good group of even 10 shots, or just have a bad day and shoot poorly. I'm more interested in how consistent my 3 shot groups are over multiple range trips. Ten strings of 3 shots over weeks or months tell me more than 3 strings of 10 shots all done the same day.

As a hunter I'm not going to fire more than 3 shots at a game animal. When you get into longer strings you start having trouble concentrating for that long and you have to deal with barrels heating up. None of which will be a factor for me hunting.

Something I've never done, but a suggestion I read about on a shooting forum was to place a target at 100 yards. Fire ONE shot at the target, only one, and the 1st shot of the day from a cold barrel with no warm-up shots. Then take that target down, save it and repeat that the next range visit. After 5-10 range visits you'll have 5-10 shots on one target. As a hunter that will tell you what you need to know.

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This is a very good post; especially the third paragraph. Spot on. The last paragraph is something that I, along with irishlad, have done when I use to hunt. Can be very telling.

3 shot groups have been a standard for measuring hunting groups, accuracy, and precision for many years and I believe it is still relevant….for hunting shooting purposes.

I don’t know about other reasons for group shooting…or at least haven’t researched or pondered them so I’ll let others comment in that regard.

Ammo cost plays a role for me. For center fire rifle, typically 3 round groups my standard (maybe except for 556/223 where a 5 round group would be called for).

22lr is a whole different animal.

earlthegoat2 said:

3 shot groups have been a standard for measuring hunting groups, accuracy, and precision for many years

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The first mention of 3 shot groups that I recall was the Weatherby guarantee of three shots in 1 1/2" a good many years ago.

I am not a gun scientist. I'm just a guy that enjoys shooting, particularly long range rifle shooting. When me and my shooting partner chrono his new handloads we usually shoot 8-10 round groups to get an average to build our DOPE cards from. If we find the data from the DOPE cards is off we will go back and shoot another group or two and refine it.

I don't know what the shooters the OP is refencing use their 3 or 5 round groups for except to show how "great" their skills are on their Youtube channels. Unless they have their rifle locked down into a shooting sled they don't know if the groupings represent the capabilities of the rifle or of their own shooting shortcomings. For the folks I instruct in long range shooting I spend a lot more time working on their technique than I do on testing out the gun's ability to shoot tiny groups. I run across and hear from so many shooters (almost all men) who claim they print cloverleaf patterns at 100, 200, 300 yards but rarely do I see that when they come out to shoot with me.

On the other hand I have a lot of first time shooters who have never fired a rifle (mostly women) who after a few hours of instruction on technique and ballistics are able to hit out to 1000 yards by the end of the day, with my rifles and most times theirs depending on the rifle they bring.

Repeatability = Accuracy.

God preserve us from mathematicians.

As @mcb points out, two five-shot groups are essentially the same as a ten-shot group, etc. - and in fact I'd say slightly better*, at least in some circumstances - so...

And along the same lines, ten three-shot groups are roughly the same as a thirty-shot group. I'd say a fellow who averages the results of ten three-shot groups has a fair idea what is rifle is capable of doing. The issue, of course, is that a lot of folks look at the best of those ten groups, discount one of the holes as a "flyer", and then report that his SKS is MOA.

The benchrest folks, who are still (as far as I know) leading the way, use five shot groups for much of their competition - but they use aggregates of multiple five shot groups to declare winners and losers. For my money, that's still a fine way of measuring accuracy.

*True hunting accuracy is best measured with a "running group". Upon arriving at the range, get everything set up, roll out a fresh target - at 200 yards, if you are a true masochist - and put the very first shot from the gun into that target. Then roll it up, put it away, and leave it for the next range session, where you'll do the same thing. After you've got at least ten holes in the target, you'll have a thorough understanding of what your gun can do in the hunting field. It almost certainly will be a pretty sorry-looking target, especially compared to your best three shot group with one "flyer" marked out. And of course, the hardened seeker of truth should repeat the experiment, but from realistic field positions, rather than from the bench...

The problem I see with guys judging loads on small groups in any’ number of shots is that they are not looking at location of impact which is the most important. It doesn’t matter to me if the load shoots a1 inch group at a thousand yards if it doesn’t repeat point of impact from day to day. It’s important to complete the load development process and not just stop on a small group and call it good. If a powder bullet combination isn’t favorable it only takes one ladder to disqualify a combo