.0077" -- Smallest 5-Shot Group In History

[gunsandgunsmithing]

Single groups are measured to the nearest 1/1000th, not 1/10000th. Why this record is listed as .0077 is not statistically valid. I know that it was sent to records judges and the .0077 was an average, but that still does not make it valid.

I don't understand what you're saying there James. Yes, as I understand it, the 4th digit is from the average of all record committee members' measurements. What's not valid about that I guess is what I mean.

 

[jelenko]

Maybe just that the group should be reported as 008 - i.e., measured to the nearest thousandth?

 

[expiper]

I was just reminiscing about the 70's and the people and events then,,,notice at the top of the target is Jess Corders signature ,,,,he loaned me a rifle to get started in Benchrest ,,,,he was on the measurement committee at that time and said that when he got the target it had been handled a lot and had absorbed a lot of moisture here in the east (West Virginia) and when he did the measurement the individual holes in the sighter measured .009" just like the 5 shot group did,,,the moisture in the west where it was shot was low ,prolly 30% or less,,,and the moisture here was 90% or more and made the paper (and the hole) swell ,,,,so it was probably a true zero group,,,,,Roger

the story goes--mac was up in montana a week or two before this and shot 4 shots in 012 and thought he was missing the target and held over and inch and shot number 5 made the group around one inch !!!!

 

[jamesdmock]

I don't understand what you're saying there James. Yes, as I understand it, the 4th digit is from the average of all record committee members' measurements. What's not valid about that I guess is what I mean.

The record group is not .0077 but .008 or perhaps .007.

 

[xr650rRider]

The record is what it is. It is displayed to ten thousandths because it is a measured average between committee members.

4.22.3. The Regional Director measures the target/s, checks the backer/s, and if the
measurement is close, within .009”, sends the target/s, backer/s, 1 copy of the
registration card, and an NBRSA World Record Submission Form properly filled out, to
the Chairman of the Measurement Committee. The Regional Director will retain one
copy of the registration card for regional file. If the measurement is not close, the
Director will return the target/s, backer/s and the 2 copies of the registration card to the
Competitor.
4.22.4. The Chairman checks the target/s, counts the holes in the backer, makes sure all targets
and backers are signed by 2 Match Officials, and checks the information on the
registration card. The Chairman measures the target(s) and if this measurement is
greater than .015 of the World Record, the Chairman returns the target(s) to the
Competitor. If everything is found to be in order, he covers up the range scores,
measures the target/s, records the scores, assigns a number to each target, and then
sends the target or targets, with the proper forms, to the first member of the Measuring
Committee. If there is a problem with a backer or backers, he also sends them along
with the targets.
4.22.5. Targets: The target/s will be measured by 3 of the 4 Committee Members. A Committee
Member residing in the same Region as the person who shot the target/s should not
measure the target/s. Those chosen to serve on this Committee need not necessarily be a
Director, but should be an NBRSA member who qualifies as a good scorer. Each of the
4 Scoring Committee Members should be from a different region. If a Member of the
Scoring Committee holds the current record, he should step aside and the Records
Committee Chairman should appoint someone else to score the “possible world record”
target so that no one could say that a “possible world record” was intentionally scored
wrongly.
4.22.6. The Committee Member measures the target/s, records the scores in his own records
and on the form, and checks any backer or other problem. He then sends the completed
form back to the chairman and sends the target/s to the next Committee Member. When
the last Committee Member has measured the target/s, he sends the target/s and
completed form back to the Chairman.
4.22.7. The Chairman then records the scores of the 3 Committee Members (range
measurement is not included), computes an average of .0001 inch on individual groups
and .0001 inch on aggregates, and that score is the official measurement

 

[gunsandgunsmithing]

The record is what it is. It is displayed to ten thousandths because it is a measured average between committee members.

4.22.3. The Regional Director measures the target/s, checks the backer/s, and if the
measurement is close, within .009”, sends the target/s, backer/s, 1 copy of the
registration card, and an NBRSA World Record Submission Form properly filled out, to
the Chairman of the Measurement Committee. The Regional Director will retain one
copy of the registration card for regional file. If the measurement is not close, the
Director will return the target/s, backer/s and the 2 copies of the registration card to the
Competitor.
4.22.4. The Chairman checks the target/s, counts the holes in the backer, makes sure all targets
and backers are signed by 2 Match Officials, and checks the information on the
registration card. The Chairman measures the target(s) and if this measurement is
greater than .015 of the World Record, the Chairman returns the target(s) to the
Competitor. If everything is found to be in order, he covers up the range scores,
measures the target/s, records the scores, assigns a number to each target, and then
sends the target or targets, with the proper forms, to the first member of the Measuring
Committee. If there is a problem with a backer or backers, he also sends them along
with the targets.
4.22.5. Targets: The target/s will be measured by 3 of the 4 Committee Members. A Committee
Member residing in the same Region as the person who shot the target/s should not
measure the target/s. Those chosen to serve on this Committee need not necessarily be a
Director, but should be an NBRSA member who qualifies as a good scorer. Each of the
4 Scoring Committee Members should be from a different region. If a Member of the
Scoring Committee holds the current record, he should step aside and the Records
Committee Chairman should appoint someone else to score the “possible world record”
target so that no one could say that a “possible world record” was intentionally scored
wrongly.
4.22.6. The Committee Member measures the target/s, records the scores in his own records
and on the form, and checks any backer or other problem. He then sends the completed
form back to the chairman and sends the target/s to the next Committee Member. When
the last Committee Member has measured the target/s, he sends the target/s and
completed form back to the Chairman.
4.22.7. The Chairman then records the scores of the 3 Committee Members (range
measurement is not included), computes an average of .0001 inch on individual groups
and .0001 inch on aggregates, and that score is the official measurement

This is how I see it too. To say otherwise would imply range measurement is what is used and that's just not the case. For example, what if the range measurement was either bigger or smaller but still sent in as a record. The committee measurement would seem to be all there is left to go by.

 

[Ned Ludd]

The point that was being made was that IF the group size was only measured to .001" accuracy, then adding up several different measurements accurate to the third decimal place and coming up with a 4th decimal place in the average value is meaningless. In such a case, James is correct, the true value would be .008". You can't create accuracy to an extra significant figure that simply wasn't present in the original mneasurements. They can certainly make the rules as they wish and state that that is how it's done, but that doesn't make it a "valid" number. So the question I have is does anyone know the actual degree of accuracy to which these measurements are made? In other words, is it to three decimal places or four?

 

[D Coots]

The current record can never be broken if I understand the rules correctly. The new possible record has to be within .009 of the old record of .0077

Time to change the rule of measurements submitted to the rules committee.

 

[xr650rRider]

So the question I have is does anyone know the actual degree of accuracy to which these measurements are made? In other words, is it to three decimal places or four?

I believe it states pretty clearly in 4.22.7 that it is measured by committee members to .0001"

If you open some of the PDF's of groups, most are measured to .0001"
https://internationalbenchrest.com/records/group

If your shooting a normal match and haven't approached a record, then .001" is the range measurement. Doesn't need to be any smaller. But for a tie-breaker or a record, then it is measured more precisely. So the world record was measured by multiple people to .0001" and averaged, so it is a valid number.

 

[xr650rRider]

The current record can never be broken if I understand the rules correctly. The new possible record has to be within .009 of the old record of .0077

Time to change the rule of measurements submitted to the rules committee.

Within .009". So if you shoot a group that approached the record it would be sent in to be measured. You could shoot .016" and it would be sent to be measured by committee.

 

[urbanrifleman]

The previous record was the "untouchable" .009" group shot by Mac McMillan in 1973:

View attachment 1266141

Mac’s .009″ group was the “Holy Grail” of rifle accuracy. This .009″ record was considered by many to be unbreakable, a record that would “stand for all time”. Well, it took 40 years, but Mike Stinnett finally broke Mac’s record with an even smaller group in 2013. Stinnett’s NBRSA record .0077″ group now stands as the smallest 100-yard group ever shot in registered benchrest competition.

Here is the record certificate originally issued to Mac McMillan. We've been told Mac was shooting a .222 Remington:

View attachment 1266142

I would be very interested to know how that rifle was built. How it was chambered. Etc.

 

[urbanrifleman]

The bullet is seated only 0.12″ into the case with zero freebore.

Kind of shoots down that shove it way down into the neck philosophy.

 

[Ned Ludd]

I believe it states pretty clearly in 4.22.7 that it is measured by committee members to .0001"

If you open some of the PDF's of groups, most are measured to .0001"
https://internationalbenchrest.com/records/group

If your shooting a normal match and haven't approached a record, then .001" is the range measurement. Doesn't need to be any smaller. But for a tie-breaker or a record, then it is measured more precisely. So the world record was measured by multiple people to .0001" and averaged, so it is a valid number.

It doesn't say "measured" to .0001, it says "computes". I take that to mean they add up multiple measurements taken to a lesser accuracy then compute the final value out to four decimal places. If so, that is meaningless, as I stated earlier. If someone is really measuring group size to .0001", I'd kinda like to know how they're doing it.

 

[jelenko]

The current record can never be broken if I understand the rules correctly. The new possible record has to be within .009 of the old record of .0077

Time to change the rule of measurements submitted to the rules committee.

I read that differently.
'Within' I read as 'less than' => the new possible record needs to be less than .009 from the current record.

For example, .005 is .002 away from .007 and is less than .009 away from .007 => it meets the criteria to be measured for a new record.

 

[jelenko]

It doesn't say "measured" to .0001, it says "computes". I take that to mean they add up multiple measurements taken to a lesser accuracy then compute the final value out to four decimal places. If so, that is meaningless, as I stated earlier. If someone is really measuring group size to .0001", I'd kinda like to know how they're doing it.

I am thinking the same. Without something firm to reference, even if you used a micrometer, how could you expect to accurately place it within .0001?

Maybe an app that uses math to find the 'edge' of the holes? But, are the edges in paper well enough defined for .0001?

 

[D Coots]

Within .009". So if you shoot a group that approached the record it would be sent in to be measured. You could shoot .016" and it would be sent to be measured by committee.

My mistake....

 

[xr650rRider]

It doesn't say "measured" to .0001, it says "computes". I take that to mean they add up multiple measurements taken to a lesser accuracy then compute the final value out to four decimal places. If so, that is meaningless, as I stated earlier. If someone is really measuring group size to .0001", I'd kinda like to know how they're doing it.

They are probably just guessing. Just do away with measuring and hand out participation awards.

 

[gpoldblue]

The current record can never be broken if I understand the rules correctly. The new possible record has to be within .009 of the old record of .0077

Time to change the rule of measurements submitted to the rules committee.

Maybe records should be set like those of Land Speed Records at Bonneville.....time/speed has to be a two
way average....that is,be backed up within a certain period of time,otherwise it is not a record.

 

[butchlambert]

Maybe records should be set like those of Land Speed Records at Bonneville.....time/speed has to be a two
way average....that is,be backed up within a certain period of time,otherwise it is not a record.

I'm kinda disappointed in you guys. Didn't they have math in school when you grew up!
Try this as an example. 4 guys measured the target and it was the average of the 4.
.006"
.009"
.007"
.009"
_______
.031
divided by 4 equals
.0075"
Wow! That may be where the 4th place came from.

 

[DaveTooley]

That was a long time ago and I don't know anyone who is still around from then. They may have measured to the half thou. As someone who was on the IBS records committee for a lot of years we worked to the thousandths and the math went to 4 places.
Seems like an argument in search of a topic.