Number of shots in a group.

[dahermit]

How many shots should be included in a group for the purposes of evaluating a load, the accuracy potential of a rifle, or just boasting?

[brickeyee]

At least five, and ten would be better.

[Pahoo]

purposes of evaluating

Three; make you adjustmnents then three more till your confidence is satified.. .

I then finish with five to document.


Be Safe !!!

[GURU1911]

THE LATE JOYCE HORNADY (founder of Hornady Bullet Company) RECOMMENDED LOADING & FIRING PAIRS OF "TEST LOADS" OR 2 SHOTS OF FACTORY AMMO, TO EVALUATE AMMO / BARREL COMPATIBILITY.

REASON: IF 2 CAREFUL SHOTS ARE TOUCHING, CLOSE TO TOUCHING, OR THEY WENT THROUGH THE SAME RAGGED HOLE, THEN THE BARREL LIKES THAT BRAND OF FACTORY / HAND-LOAD RECIPE. IF THE HOLES ARE TOO WIDELY SPACED APART (> 1.000" CTC) @ 100 YARDS, THEN YOU ARE SIMPLY WASTING AMMO IN THAT PARTICULAR RIFLE.

IF YOU FIND A BRAND OF FACTORY / HAND-LOAD RECIPE THAT THE BARREL GROUPS THE BEST, THEN FIRE A FEW MORE SHOTS TO CONFIRM YOUR ASSUMPTION & THEN ADJUST YOUR SCOPE TO IMPACT 2.5 TO 3.0 INCHES HIGH @ 100 YARDS. DO NOT CHANGE BRANDS OF FACTORY OR ALTER YOUR HAND-LOAD RECIPE---SIMPLY DUPLICATE A LARGE AMOUNT OF AMMO & LEAVE WELL ENOUGH ALONE.

GURU1911

[dahermit]

REASON: IF 2 CAREFUL SHOTS ARE TOUCHING, CLOSE TO TOUCHING, OR THEY WENT THROUGH THE SAME RAGGED HOLE, THEN THE BARREL LIKES THAT BRAND OF FACTORY / HAND-LOAD RECIPE.

Can that happen just by chance? If so, will a very accurate rifle be more likely to and do that more frequently than an inaccurate rifle?

[Jim243]

How many shots should be included in a group for the purposes of evaluating a load

First shot for function, second shot for sighting scope, three shots for group. I load 5 rounds for each level of powder when developing a load. You might say that's 5 shots, but only three for grouping.

the accuracy potential of a rifle

Generally ten shots for evaluating the rifle.

or just boasting?

One shot for boasting, it only takes one for a kill. (one shot,one kill)

Jim

Can that happen just by chance?

No it doesn't.

[m&p45acp10+1]

For me there is a very big it depends on which gun it is.

Grampa's old 30-30 has never fired 2 shots at the same target. I can not count how many lteral tons of venison that rifle has put in the freezer over the past 50+years.

Others 3 shots for a hunting rifle. The most important being the first cold barreled shot.

Varmint rifles go for 10 shot groups. Simply because they are gonna be used in a situation where there are going to be a lot of shots taken in a a very short span of time.

[TXGunNut]

I've been mislead by three shot groups but they will suffice for most purposes in a rifle and load that is known to be accurate. For load development testing I load ten rounds and fire two five round groups for careful evaluation. Some rifles and pistols can be quite a handful so a five shot group sometimes contains a flyer. I can generally call it and exclude it from the group.
I respectfully disagree with Hornady about groups over 1" being a waste of ammunition. For his rifles and loads, yes. For me and my rfles & loads, no. Some rifles and shooters are simply not capable of that level of performance and most hunting and shooting situations don't require it. I have rifles that are easily capable of it and even .5 MOA (even when handicapped by me!) but some that most likely aren't. I'd be quite surprised if my 94 Trappers in thutty-thutty and .45 Colt were capable of MOA but I wasn't looking for a tack-driver when I ran across them.
I'll be testing cast boolit loads today in a 45-90 Sharps, a 45-70 Guide Gun and .35 Rem in a 336 as well as a T/C Contender pistol. Of the three only the Contender is a proven MOA performer, the Guide Gun and 336 are close enough for me. I'd be very surprised but very happy to see an MOA group through my spotting scope later today but I won't be too disappointed if I don't.

[Hog Buster]

“Can it happen just by chance?”

One shot ? You bet. Even a blind squirrel finds an acorn now and then.

Two shots? This calls for a tie breaker. Plus usually a wager from your shooting companions.

Third shot? Tie breaker and money maker. Collect cash, or pay up.

More? You have bragging rights. Have at it.

But, remember, only the first shot counts when hunting. Any following shots are just to cover your mistakes.

[dahermit]

“Can it happen just by chance?”

One shot ? You bet. Even a blind squirrel finds an acorn now and then.

Two shots? This calls for a tie breaker. Plus usually a wager from your shooting companions.

Third shot? Tie breaker and money maker. Collect cash, or pay up.

More? You have bragging rights. Have at it.

So, it is your opinion that the chance of three touching shots is always an indication of accuracy? If that is so, how do you explain why five-shot groups are always so much bigger than three-shot groups?

But, remember, only the first shot counts when hunting. Any following shots are just to cover your mistakes.

"...Evaluating rifle, loads...", is not much about hunting, was meant to focus on accuracy only.

[Hog Buster]

"So, it is your opinion that the chance of three touching shots is always an indication of accuracy? If that is so, how do you explain why five-shot groups are always so much bigger than three-shot groups?"

Shooter error. It's hard to impossible to be able to do the many things necessary in the same order, at the same time, under the same conditions to achieve the same shot multiple times. Head and hands don’t always necessarily work in concert for every shot. The probability that you are unable to do so far outweighs the probability that you can. More shots, more room for error.

Of course this isn't considering the rifles accuracy potential, or lack thereof, which also plays a major part in grouping.

Sorry, I’m a hunter so evaluating accuracy for that reason is always paramount to me.

[Charlie98]

With the caveat that I'm a casual paper poker and beer can ventilator... not a hunter (one shot) or a benchrester (one shot, take a lunch, one shot, take a coffee break...) I think a 5-shot group is a reasonable amount to determine median accuracy for general purposes.

[Clark]

If you know what your are doing, you fire one shot at the range, adjust the rifle, and leave.

None of us know what we are doing.

So I fumble around with 3 shot groups on high power hunting rifles, and 5 shot groups with varmint rifles.

[TXGunNut]

If that is so, how do you explain why five-shot groups are always so much bigger than three-shot groups?-dahermit

When I'm having a good day they aren't necessarily. If I'm shooting a really good group I'll get excited and blow it inside of 5, certainly ten rounds, but that's the loose nut behind the trigger. I had a rifle that would quite often shoot a very good 3-shot group. Next 3-shot group was either disappointing or possibly another good group, just not in the same location as the first "good group". This isn't uncommon so I feel better about a 5 or 10-shot group. It'll never be smaller than a 3-shot goup but it doesn't have to be larger.
If I'm sighting in a hunting rifle with a known good load three shots work just fine. With one remarkably good rifle I'd simply staple a business card up at 100 yds, fire one shot (generally 1/4" low of center) and I was ready to go hunting.

[wingman]

How about 30 rounds fired in 10 groups of 3 then average. if my average remains at or below .600 at one hundred yards I regard it as a good rifle. I see no disadvantage using 3 or 5 shot groups if average is applied.

I've always use the average method it gives me more knowledge of a gun/ ammo and my abilities.

[Hog Buster]

Back in my U.S.M.C. days, long ago, those of iron men and wooden ships, we were taught a method of sighting in called Triangulation. It was nothing more than firing three shots, then attempting to move the center of that group to the center of the target with the appropriate number of clicks. A couple of tries and you were in the black. This was standard procedure for many years, hence the advent ot the three shot shot group.

I’ve used three shot groups for years with much success. I’ve also shot groups with more than three shots, sometimes many more. Most times larger but never smaller. Depending on the shooters ability, plus a profusion of other circumstances, three shots may not seem adequate to all at the time. However, generally speaking three will get the job done.

It’s so nice to see that little three leafed clover that many are not willing to take the 3 to 1 chance that the next one might be a flyer, myself included....

[wncchester]

Depends on how accurate you want your evaluation to be. Small numbers vary a lot, from accidentally small to an honest much larger groups. Thing is, if we want to actually KNOW what our rig is capabile of we must include all the rounds fired, not just a small sample that's statistically almost irrelivant.

I use small groups - usually five - for testiing but I count my accuracy as whatever MOA the total spread is. Averaging small groups simply deludes ourselves about what our dependable accuracy really is!

[FrankenMauser]

Useful group -> Three shots.
Meaningful group -> Five shots.

Three-shot groups skew the data rather substantially, with even a single flyer.
Five-shot groups offer significantly better averages.
Ten shot groups are where you get into a proper statistical analysis.


...But most of us are too cheap (or too poor) to use ten-shot groups for everything, especially for load development.

I fire five-shot groups when I can; but, often, have to fall back to the not-so-helpful three-shot groups.

[Brian Pfleuger]

I prefer 5 but I often run out of time, patience or ammo.
Even putting 3 rounds in a small spot is not easy at longer ranges.
Mostly I shoot 3 shot groups. No one else knows for sure if I shot at 10 yards or 100 anyway and I'm doing it for me, not them. I don't care if they're impressed or like my decisions or not.

[4runnerman]

5 in my book.Last week did 20 loads of 5 rounds.Found 4 that were very good,Now i will load 10 of each of those 4 and see if it can be duplicated over and over or if i was just having a good day

[Lost Sheep]

One day at the range I was a guy shooting at a can he had placed on the berm that served as a backstop, about 25 yards. He was hitting all around it, but had yet to put a hole in it. He was me watching and I asked, "May I try?"

I opened my revolver (6" Dan Wesson .357), dropped one round in the cylinder, put my back against a post and used an isosceles hold and drilled it in the lower right. The can flopped over on its side and rolled down the berm.

He wasn't so upset that I outshot him, or even that I had only loaded one round to do it. He had to run all the way out to set the can back up where he could see it again.

Group size depends on statistics. You are taking a sample of all the population of trajectories your gun will shoot (with those particular conditions and that particular load) in the near (before barrel wear takes place).

One is nonsense

Two may be chance (tight or loose)

Three shows tendency (allows you to identify a flyer, maybe)

Four tends to confirm the conclusion you drew from three.

Five assures you didn't waste the first four drawing an incorrect conclusion.

You put in a lot of time making three rounds per test. Then shoot them. It makes sense to me to put in a little bit more time to increase the certainty. Three is minimally sufficient. Four increases certainty. Five makes pretty sure you didn't waste your time.

There is a saying, "The man with one watch is always certain of the time. The man with two watches is never quite sure." To which I add, "With three, he has an idea which of the first two is the correct one."

Each round you add to your grouping testing, the more precise are your conclusions. How much precision do you want? That will tell you how many rounds you need.

A problem arises when you realize that every bullet you fire changes your barrel minutely and all that shooting of "extra" bullets makes the earlier bullets less relevent to the way your barrel performs now.

Lost Sheep

[Crankylove]

I will usually go for groups of 5.

3 shot groups if I ran out of compenents, or if testing a wide range of powder charge. 3 shots should tell me if it is worth more effort to pursue that load or not.

[GURU1911]

OLD SCHOOL THINKING:

ACCURACY----AN INDICATOR OF THE SHOOTER'S ABILITY TO SHOOT GROUPS ON A TARGET AT A GIVEN DISTANCE, UTILIZING TYPICAL SHOOTING POSITIONS (ie: Standing, Sitting, Kneeling, & Prone).

PRECISION----A SHOT GROUP MEASUREMENT EXPRESSED IN THOUSANDTH'S OF AN INCH (0.000") CENTER-TO-CENTER (CTC) ON A TARGET AT A GIVEN DISTANCE, TYPICALLY FIRED FROM A STABLE SHOOTING SURFACE, AS A MEANS TO EVALUATE THE COMPATIBILITY & QUALITY OF AMMUNITION, BARREL, TRIGGER PULL, & THE OPTICAL SYSTEM. THE GOAL IS TO ELIMINATE AS MUCH HUMAN INTERFERENCE AS POSSIBLE.

IN 1997, I HOT-RODDED A REM MODEL 700 IN .270 WINCHESTER, & THEN OBSERVED MY CLIENT FIRE A 3-SHOT CONCRETE BENCH-RESTED GROUP USING MY STEEL SHOOTING JIG @ 100 YARDS. THE AMMO WAS 130 GRAIN WINCHESTER WHITE BOX. OPTICS WERE A 3-9 BURRIS FULLFIELD. BASES & RINGS WERE LEUPOLD DUAL-DOVETAIL. THE GROUP MEASURED .090" CTC &
HE QUICKLY STATED "THIS AIN'T ME. ITS THE COMBINATION OF ALL THE PARTS OF THE PUZZLE WORKING TOGETHER---WOW" OBVIOUSLY WE BOTH SAW THE NEED TO EXPEND NO ADDITIONAL AMMUNITION. THAT FOLLOWING HUNTING SEASON, THAT AWESOME SHOOTING MACHINE HARVESTED 18 DEER IN THE HANDS OF 12 DIFFERENT SHOOTERS, USING ONLY ONE ROUND PER KILL.

GENTLEMEN, THAT IS THE DIFFERENCE BETWEEN ACCURACY & PRECISION, AS I WAS TAUGHT & HAVE PERSONALLY EXPERIENCED OVER THE PAST 50 YEARS.

GURU1911

[Kevin Rohrer]

I shoot 3-shot groups for testing loads and 5-shot groups for determining final sight-in and final load testing.

[zippy13]

It seems there's a consensus that 10 is over doing it. I prefer 5-shot groups.