Th measuring of group size

[mtmuley]

Recent days of talking with friends and perusing other sites has me confused about how to measure a group of a string of shots that a certain rifle will shoot. How do YOU guys here measure "group" size? I have heard to take outside to outside of the bullets impact, and subtract the bullet diameter. Or, take center to center of the furthest impacts. Help. mtmuley

 

[britz]

you've pretty much got it. You take the farthest two holes in a group (all of the shots in the group, not the best three!) and you measure to the outsides of these two and subtract one bullet diameter to give you the center to center group. Not official but close enough!

 

[James Jones]

Its alot harder to measure the center to center of the shots so i measure the furthest outside edges and subtract the bullet diameter.
Note though that if you take a paper target and flatten it out on a desk that the actual bullet hole is smaller than the bullet diameter but their will be a slight grey ring just around it , use your caliper and adjust it from the actual hole in the paper out till you reach the bullet diameter and make a not as to where this falls out then measure the group from the furthest outside edges of that grey ring then subtrack the bullet diameter. I have hurt alot of guys feeling by doing this but that the accurate way to get the group size.

 

[shootinfool]

I have always used a pair of calipers to masure the outside to outside of the darker ring, not the acutal hole in the paper, of the furthest two shots, then simply subtracting the bullet diameter. This is the easiest and in my opinion the most accurate way, like james jones said, it is harder to find the exact center of the bullet holes and then masure the center to center group.

 

[eddybo]

I measure the size of an individual bullet hole then zero the calipers w/o moving them.......then just measure the outside to outside. Same thing no math involved.............then I just fudge a little from there

 

[Adam Lee]

i just guess! lol

 

[mtmuley]

Thanks guys. The help is appreciated. mtmuley

 

[gbraach]

1 moa group???

So I got a follow up question for whoever can help.

If your rifle shoots 1 moa groups. Shooting at a hundred yards, is your group size 1.05 inches (moa = diameter of group) or is your group size 2.10 inches (moa = radius of group)?

 

[James Jones]

one minute of angle at 100yds would be a 1" group measured by the DIAMTETER , measuring outside to outside of the widest spread minus the bullet diameter