JFrank
Member
I can't speak for short range NBRSA or IBS but Long range has no app scoring just center to center measuring.
How do you measure group size??
- Thread starter Russell13
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chicharrones
needs more ammo
JFrank
Member
What organization uses this method?
You see it on westerns as a kid, but you hit a bottle just right, it will fly 15’ in the air! LolHonestly—
Hitting a plastic orange juice bottle, mostly at 25 yards (Action Pistol), sometimes at 50 yards.
-The bottle jumps into the air-
Not kidding. It’s only about having fun.
Very seldom have anybody with whom to shoot anyway.
PWC
Member
For competition used to use caliber "plugs" with built in magnifier, to find best/worst edge. Sometimes when it looked like a shot was missed, turn the target over and recounting from the back is more clear.
Informally, center to center, inside edge to edge, outside edge to edge, group outside edge to opposite side inside edge, all work.
Remember, statistics don't lie, but they can be manipulated. Just be consistent in method application.
Informally, center to center, inside edge to edge, outside edge to edge, group outside edge to opposite side inside edge, all work.
Remember, statistics don't lie, but they can be manipulated. Just be consistent in method application.
Offfhand
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A specialized instrument used in registered short range (100,200,300yds) benchrest competition utilizes magnification lens over appropriate rings. When used correctly measures group sizes to closest.001" Accurate measurement is important in benchrest competitions because the difference between winning and losing may be only a tiny few thousands. Here is the tool I use and pic of scorer at a major tournament using a similar instrument.
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doubleh
Member
Post #19 describes the simplest method. I only compete with myself and that gets it done when I want to measure an especially good group. My MK I eyeball is still fairly well calibrated though and unless it's really a small group I go with that.
Jim Watson
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Archie
Member
Not being concerned with best rest competition, I made up a computer generated group of concentric rings. The rings are one inch diameter then one inch larger to eight inches. Then printed the concentric rings on a transparency. I can take a copy to the range in a folder and use it on the target to give me a quick answer to how big the group.
Center the rings on the center of the group and slide it around until all the shots are contained in the same ring. (Ignore the aiming point. It has no bearing on group size.) If all the shot holes are within the two inch ring, it is at most a two inch group. For determining which group is 'best' when working up loads, this is quite accurate and much quicker than being concerned about center of each hold and measuring with a micrometer or tape measure.
Please note this does not remove the need to adjust the sight (iron or glass) to center the group on the target, either paper or biological.
Center the rings on the center of the group and slide it around until all the shots are contained in the same ring. (Ignore the aiming point. It has no bearing on group size.) If all the shot holes are within the two inch ring, it is at most a two inch group. For determining which group is 'best' when working up loads, this is quite accurate and much quicker than being concerned about center of each hold and measuring with a micrometer or tape measure.
Please note this does not remove the need to adjust the sight (iron or glass) to center the group on the target, either paper or biological.
lysanderxiii
Member
if you really want to shoot small groups, mean radius instead of extreme spread
That doesn't reduce the group's size, just the number that represents it . . .
herrwalther
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I carry change in my pocket sometimes when I go to the range. Not change like chicharrones though, just normal change. Quarter, nickel, maybe a dime. That is all I really use to compare.
Trey Veston
Member
I do center to center. But, I no longer compete in actual matches where such things matter.
The bigger questions is how many rounds in a group?
With pistols, I always used a 5-shot group at 25 yards as a standard.
With rifles, I always did 3-shot groups at 100 yards as a standard. I guess because in my world, rifles are used for hunting, and most hunting barrels lose accuracy after 3 shots due to heating up. Match barrels can maintain consistency for 5 shots, but thinner and lighter hunting barrels are done at 3.
Hence, 3-shot groups for rifles.
The bigger questions is how many rounds in a group?
With pistols, I always used a 5-shot group at 25 yards as a standard.
With rifles, I always did 3-shot groups at 100 yards as a standard. I guess because in my world, rifles are used for hunting, and most hunting barrels lose accuracy after 3 shots due to heating up. Match barrels can maintain consistency for 5 shots, but thinner and lighter hunting barrels are done at 3.
Hence, 3-shot groups for rifles.
Varminterror
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This is really the gap for me. I’m shooting 20 calibers any given season, so owning a set of plugs for all don’t make much sense. I can’t eyeball centers, floating in space, nearly as well as I can reference an edge, so without plugs, I simply measure O-O, then subtract the diameter of a hole (example: the holes on the paper I shot last week are .225-.228”, despite the fact a .243” bullet passed through it).
barnfrog
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MOGCL?
AMraider
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- Apr 1, 2019
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First time shooting a Sestroryetsk M91 from 1916. Bore is in bad shape and the crown is more like a Blunderbuss. It must have suffered severe steel cleaning rod use. 10 rounds at 100 yards = No hits. 10 rounds at 50 yards = 1 hit.Sidways. 10 rounds at 25 yards at BIG target = MOGCL. : )
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