Meausure Groups
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If you don't have a tool as Chuck mentioned, here's what I recommend. First measure the outside edge of 5 or 6 SINGLE bullet holes that are nice and round, and in the same paper/cardboard as your group target. Try to include the same amount of black fringe every time. OK, write down the average of the outside diam of those holes.
Now measure the extreme outside edges of the group, including the same amount of black fringe you did before. Now subtract the single-hole average you wrote down,which will be less than .243", and more like .220").
With a cloverleaf type group this is generally easier and more reliable than trying to measure center to center. It also accounts for different hole sizes in different types of target materials.
I've noticed that a pretty high percentage of newbies don't get the measurement right at all. They tend to underestimate by ignoring the black edge and then subtracting a full .243". This conveniently shrinks their group by as much as 0.140".
I saw one guy,on another gun board) claiming a .189" group for a .308" target when you could clearly see two full bullet holes side by side--touching but not overlapping. Acknowledging that each bullet hole was a bit smaller than .308", that target was probably about .280".
Now measure the extreme outside edges of the group, including the same amount of black fringe you did before. Now subtract the single-hole average you wrote down,which will be less than .243", and more like .220").
With a cloverleaf type group this is generally easier and more reliable than trying to measure center to center. It also accounts for different hole sizes in different types of target materials.
I've noticed that a pretty high percentage of newbies don't get the measurement right at all. They tend to underestimate by ignoring the black edge and then subtracting a full .243". This conveniently shrinks their group by as much as 0.140".
I saw one guy,on another gun board) claiming a .189" group for a .308" target when you could clearly see two full bullet holes side by side--touching but not overlapping. Acknowledging that each bullet hole was a bit smaller than .308", that target was probably about .280".
We used to carry a target measuring tool, here at Sinclair, that was made by Neal Jones, over at Custom Products. You can call Neal at 814-763-2769, if you prefer, or you can order the target measuring tool direct from him at www.nealjones.com and Neal will get that out for you.
Cordially,
Bob Blaine
Cordially,
Bob Blaine
I stand corrected and duly whipped with the proverbial "wet noodle"! All I have to do is to have my fingers move the way my mind is!
Cordially,
Bob Blaine
Cordially,
Bob Blaine
I was shooting some test loads at 300 yards the other day. When I walked down to examine the targets, I was very disappointed. I was shooting 10 shot groups and it looked like crap. I was shooting on a target that had a one inch grid.
When I got home, I decided to measure the groups with a caliper,to my surprise-all of the groups were sub-moa.
They just did not look that way to the nekid,Georgia Spelling)eye.
I guess the moral of this story is, you never really know how big the group is unless you measure it. I am so used to looking and hearing about the group size that the point blank,100&200) people are shooting, that if I have a barrel that shoots just a little sub-moa, it's time to get rid of it.
I shot a poor score with this same barrel at a 1000 yard match at ORSA a couple of weeks ago, that Monday I could not wait for Pac-Nor to open to buy a new tube.
When I shoot like pig, I always look for some excuse.
It's always the arrow never the Indian!!!!!!!!
When I got home, I decided to measure the groups with a caliper,to my surprise-all of the groups were sub-moa.
They just did not look that way to the nekid,Georgia Spelling)eye.
I guess the moral of this story is, you never really know how big the group is unless you measure it. I am so used to looking and hearing about the group size that the point blank,100&200) people are shooting, that if I have a barrel that shoots just a little sub-moa, it's time to get rid of it.
I shot a poor score with this same barrel at a 1000 yard match at ORSA a couple of weeks ago, that Monday I could not wait for Pac-Nor to open to buy a new tube.
When I shoot like pig, I always look for some excuse.
It's always the arrow never the Indian!!!!!!!!
Chuck
I have all the measuring gizmos except that Hood plastic. I have found that for Range purposes a metal engineers staright edge calibrated to 1/32 of an inch gives a good quick measurement especially for informal practice.
Stephen Perry
I have all the measuring gizmos except that Hood plastic. I have found that for Range purposes a metal engineers staright edge calibrated to 1/32 of an inch gives a good quick measurement especially for informal practice.
Stephen Perry
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