How accurate is my rifle

[LR1955]

I am always reading about guys' guns that are MOA or Sub MOA or 1/2 MOA or whatever. I thought I had a clear understanding, but I read something on the internet (so it must be true) that has me confused again.

1 MOA @100 yards is 1.047". So, 1 MOA (@100yds) is a group (3 shot) that will fit in a circle less than or equal to 1.047" or 1 3/64" in diameter. Correct?
1/2 MOA (@100yds) is a group (3 shot) that will fit in a circle less than or equal to 0.5235" or 67/128" in diameter. Correct?

1 MOA @ 200 yards is 2.094". Same logic as above. Correct?
1 MOA @ 300 yards is 3.141". Same logic as above. Correct?

And so on... BTW, just to be picky, is that a measurement from the center of the bullet impact or the edge?

I'd like to know how to be able to CORRECTLY identify my rifle's capabilities (and I assume some others would too). Do you guys all know this because of military training, or did your Grandpa explain it when he taught you how to shoot? Surely I'm not the only one who missed that portion of marksmanship 101.


-mm

Mike:

To correctly state your rifle's capabilities you would need a rifle vice anchored to a very solid concrete bench so the rifle would not move when it fired. You would pull the trigger mechanically and fire a string at what ever distance you are using. Then you would figure out the mean radius of the group by careful measurement. You would then communicate the accuracy in terms of mean radius.

Of course, no one but me would understand what you were trying to communicate so guys shoot groups at a specific distance, then determine what shot or shots they want to eliminate from the measurement, and measure the remainder of the shots. For example, if I am shooting for group and call a shot that was outside my standard of performance, and it went outside that standard, I would not include it in the measure because I called it out and it went out. I do not accept the notion of a 'flyer' so if a shot doesn't go to call and is out of my standard, it gets counted. The reason why I count these 'flyers' is because something went wrong that I can't determine so it is a mechanical issue and thus part of the group size.

Whether you go center to center, edge to edge and subtract one bullet diameter, is up to you but you may want to state how you measured when you state your group size.

I go with four each, five shot strings no matter how I present the data. And, I will not shoot for group at anything closer than 200 yards. And, I will state the range where I took the group size. A rifle / ammunition combination that holds one minute at 600 yards means more than the same rifle holding one minute at 200 yards.

So, unless you want to measure a mean radius, it is up to you. Just state your process.

LR1955