Originally Posted by JGRaider
I just hunt. I'm not into competition, BR, etc so I'm going to ask a really ignorant question. Why should I care about 5 shot groups, especially when the first goes exactly where it's supposed to,and the second, and third one goes into consistently small groups?



I do it because it is an easy way to get enough shots to really have a good idea where any one will land. If we just shoot three shot groups and measure the size between the two farthest shots each time we really don't know what size target the gun is actually able to hit. That is because guns actually fire rounds into a cone. Three and five shot groups no matter how small, can be anywhere within that cone.

In other words, lets we have a gun that will put every round fired for the life of the barrel, say 2K rounds into a 1.5MOA "cone". We fire a 3 round group that is 1/2MOA. We fire another that is 3/4MOA. Then we have a flyer and a group just over 1 MOA. One more at .3MOA. Now most would say that they have a .5 MOA gun, if they do their part as that one group must have been them. The problem is that they don't realize that because they didn't shoot all the shots on one target, the first group was actually located in the upper left corner of the "cone", the second in the lower portion, the third sort of centered, and the last in the right. Even though each group was MOA or better, when overlaid on one target we get an aggregate of 1.5 MOA which is what the gun will mechanically be expected to do.


It's harder to write than to show. Below is a test I did showing just that.

The first 3 round group.
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I somehow didn't get a picture of the second but it was 5/8ths of an inch.


This is the third.

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The fourth with what seems to be a flyer....
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The fifth.
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Now it doesn't seem to be a tack driver but most would guess about a 1MOA or just over except for the one flyer. Well when we fire a 10 shot group we see that maybe that one at 3 o'clock wasn't a flyer after all.

[Linked Image]


When we look at the backer that was behind the 5x three round groups and the ten round group it's obvious that neither the far right shot or the two low shots in the 3 round targets are flyers.
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I know from shooting a 50 round composite group that the group size was within a 1/4 inch of the 10 round group. Now I have around 3,500 rounds through that gun and most of the time 3 round groups are under an inch with that lot of ammo. However if I hang a 1 MOA target I can't guarantee that it will hit it on demand. Hang a 2 MOA target and it will hit it with every round fired. That is because it is really a 1.75MOA gun/ammo combo.