Measuring a group to three decimal points is all a bunch of gun magazine hokus pokus. I dont care if they do make an outside micrometer to do it more accurately. You're measuring holes cut in a product that is highly changable due to thickness, dierction of grain, % moisture, temperature , etc. A 1/2" group is no more accurate than a .50" group or a .500 group. It's just like fluted barrels and the Browning barrel tuning thing hung on the end of the rifle... all hokus pokus.
I have to respond to this one just to clear it up.
The reason that groups are typically measured in thousandths it to be precise and when working up loads for long range it will tell you if your on the right tract.an extreme example
would be a change in group size from .500 to .475 , very hard to see with the naked eye
but .025 at 100 yards could mean 1/4 " at a 1000 yards. not much but I have seen matches
won by less than that.
What most are looking for is a significant change and the only way to be accurate is to use
an accurate method.
Even if you only reduce the overall group size by ,100 thousandths it is a more consistant
load and will hit more accuratly shot to shot.
If you are happy with a group that you can cover with a quarter then be happy but a quarter
is 7/8" and most on this site aren't happy unless they can shoot 1/2 MOA groups because of
the range.
I have also heard of a measurement of "1 Minute of buffalo" but to each his on.
Accuracy is achieved by very small steps and the only way to measure these steps is in
thousandths of an inch.
If this kind of measure was Hokus pokus then why do we measure bullet seating depth in thousandths, head space in thousandths, free bore in thousandths and most everything that
must be accurate to build an accurate rifle.
Don't be offended but if you are happy with rounding every thing off to "Close to a 1/2 inch"
fine but Some of us want to be a little more precise. close only counts with horse shoes and
hand grenades.
Just my opinion
J E CUSTOM