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Groups are sometimes hard to measure...


And yes, I totally agree with the statement that subtracting the bullet diameter from the outside to outside measurement is very "optimistic". However, guys started doing that right from the get go in this thread. I overlooked it, as this challenge isn't like a world championship or anything, it was just meant to be fun and maybe a little bragging right on your rifles. I think I've brought just about every rifle I own and entered them into the challenge. For the most part, most of my rifles have proven themselves to me as sub moa shooters. The funny thing is some of my last targets will show you guys what Tyrone, myself, probably rost, and some other guys that shoot competitively are talking about with the way you are measuring to be off just a wee bit.

Generally I just plop the damn caliper where I think the center of the hole is, and yes, that is even closer to an actual measurement than outside to outside and subtracting bullet diameter. Like these for example:

Yes, that is even closer to actual group size than subtracting bullet diameter.
To show you guys what Tyrone is talking about, lets measure some easy 3 shot group targets, because my 10 shot groups are always hard to measure...

Example 1: This is a .443" 3 shot group:


Now, when you measure outside to outside and subtract the bullet diameter, the number shrinks:

Surprisingly it shrinks quite a bit: to .407"

Example 2: Here's another 3 shot group from my Noveske. It measures .502" inside to outside, which is actual group size:


But when you lay the caliper down and measure out to out, then subtract the .224", it is surprisingly smaller:

Now, that is saying .451".

This is why I always measure inside to outside. It's a more accurate way to measure group size. If I can't measure that way, plop it down in the center of the hole. Its still more accurate than out to out measure...:

Here's a target that would be top score here, had I measured erroneously....:


Prime example:



Had I measured that way, the over all score (2 10 shot groups) would have been .497 MOA. However, In my own clear judgment, I would not be able to do that...

Hell, my Tikka T3 22-250 would be in the top 3 and kick John Hondo off of his #2 spot, and that's a brand new rifle to me. That adjusted score would be .554 moa... Just sayin