calculating group center
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Re: calculating group center
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnson</div><div class="ubbcode-body">Have you used On Target software?
</div></div>
ABSOLUTELY GET THIS! Free program, download here.
Makes finding true MOA and gives you average center to center. Group center, group height, group width...all kinds of fun stuff.
Here's a group at 1100 that shows the POA in a small green circle and the average middle of the group with a green cross hair, connected by a dashed line to show how far off my "group" is from my POA
You can change all the colors of the markings, the distance the target was set up, the caliber of bullets used, yada yada yada. In that pic, I have my bullet holes set to blue and everthing else set to gree, but I usually change it up depending on the targets color.
I use it for just about any target I shoot
This is just fictional data, but it shows some of the details you can get.
The bottom variable called "Off" shows that the "group" POI is only off the POA by Horiz .858" and Vert .665"
(I just made a WAG at 500 yds, 6" target and .308 for demo purposes)
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnson</div><div class="ubbcode-body">Have you used On Target software?
</div></div>
ABSOLUTELY GET THIS! Free program, download here.
Makes finding true MOA and gives you average center to center. Group center, group height, group width...all kinds of fun stuff.
Here's a group at 1100 that shows the POA in a small green circle and the average middle of the group with a green cross hair, connected by a dashed line to show how far off my "group" is from my POA
You can change all the colors of the markings, the distance the target was set up, the caliber of bullets used, yada yada yada. In that pic, I have my bullet holes set to blue and everthing else set to gree, but I usually change it up depending on the targets color.
I use it for just about any target I shoot
This is just fictional data, but it shows some of the details you can get.
The bottom variable called "Off" shows that the "group" POI is only off the POA by Horiz .858" and Vert .665"
(I just made a WAG at 500 yds, 6" target and .308 for demo purposes)
Re: calculating group center
This is cool.
So would this method provide a more standardize approach to calculating MOA (especially at longer distances?).
Is this the method used by most?
I just go from center impact to center (using the two furthest.
This is cool.
So would this method provide a more standardize approach to calculating MOA (especially at longer distances?).
Is this the method used by most?
I just go from center impact to center (using the two furthest.
Re: calculating group center
Well, for all intense purposes, what you're doing is close enough, but I just hate doing math. (when I don't need to)
If you're two farthest holes are 5" at a 1000 yd plate. That's not really 1/2 MOA.
This program just makes it easier to find find details down to the nuts. And all you need to know is the distance, caliber and have some way to reference the length.
The one I did with the plate, I held the bullet up because I know the exact OAL of the bullet, so I used that length, "2.865", as my reference length.
Sometimes people use the grid on a target, sometimes the distance across a target of known size.
I just like it, cause I have a folder saved of all my target and load data, so I can see if a group that was working at one time, ever starts to show significant decline.
Well, for all intense purposes, what you're doing is close enough, but I just hate doing math. (when I don't need to)
If you're two farthest holes are 5" at a 1000 yd plate. That's not really 1/2 MOA.
This program just makes it easier to find find details down to the nuts. And all you need to know is the distance, caliber and have some way to reference the length.
The one I did with the plate, I held the bullet up because I know the exact OAL of the bullet, so I used that length, "2.865", as my reference length.
Sometimes people use the grid on a target, sometimes the distance across a target of known size.
I just like it, cause I have a folder saved of all my target and load data, so I can see if a group that was working at one time, ever starts to show significant decline.
Re: calculating group center
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnson</div><div class="ubbcode-body">I think he means intensive purposes. </div></div>
How about "intents and purposes"?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnson</div><div class="ubbcode-body">I think he means intensive purposes. </div></div>
How about "intents and purposes"?
Re: calculating group center
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: fw707</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnson</div><div class="ubbcode-body">I think he means intensive purposes. </div></div>
How about "intents and purposes"? </div></div>
Finally someone gets it right.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: fw707</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: johnson</div><div class="ubbcode-body">I think he means intensive purposes. </div></div>
How about "intents and purposes"? </div></div>
Finally someone gets it right.
Re: calculating group center
Back about '77 or 78, Col Headcoah (sp), the coach of the New Mexico National Guard (later AG for the state of NM) taught me my favored method of obtaining a zero.
He would pick up score books from different shooters (those that ploted their shots that is). He would draw a line, from 12 to 6 and from 9 to 3, and count the shots in each quarter. If there wasn't the exact number of shots in each quarter, then the zero was off.
This works for correcting zero. If you notice most score or data books have a spot for zero then a spot for correct zero.
Of course if orginally obtaining a zero the same can be done on the target. Divide in quarters, adjust until you have an equal number of shots in each quarter. Of course the more shots you have, the more accurate the zero.
With the three or 5 shot groups, you normal get two close and one or more shots futher out. You seldom get a group with equal number sides of the triangle. With the methold described it doen't matter.
You fire twenty or so shots on a target, adjust until you have an equal number of shots in each quarter, you have a zero, Regardless of the quality of shooter. You may have a 2 inch group or 5 inch group. As long as you have an equal number of shots per quarter, you have a zero.
And if we use the score/data book like we are suppose to, you can go back every now and then to confirm your zero, or make adjustments as needed.
Back about '77 or 78, Col Headcoah (sp), the coach of the New Mexico National Guard (later AG for the state of NM) taught me my favored method of obtaining a zero.
He would pick up score books from different shooters (those that ploted their shots that is). He would draw a line, from 12 to 6 and from 9 to 3, and count the shots in each quarter. If there wasn't the exact number of shots in each quarter, then the zero was off.
This works for correcting zero. If you notice most score or data books have a spot for zero then a spot for correct zero.
Of course if orginally obtaining a zero the same can be done on the target. Divide in quarters, adjust until you have an equal number of shots in each quarter. Of course the more shots you have, the more accurate the zero.
With the three or 5 shot groups, you normal get two close and one or more shots futher out. You seldom get a group with equal number sides of the triangle. With the methold described it doen't matter.
You fire twenty or so shots on a target, adjust until you have an equal number of shots in each quarter, you have a zero, Regardless of the quality of shooter. You may have a 2 inch group or 5 inch group. As long as you have an equal number of shots per quarter, you have a zero.
And if we use the score/data book like we are suppose to, you can go back every now and then to confirm your zero, or make adjustments as needed.
Re: calculating group center
+1 Kraig
The most difficult zeros to refine for me are from the standing position. My method is the blind call and plot exercise where I dry fire and plot my call and then follow with live fire calling and plotting those shots too. After about 50 minutes of this I will overlay my call sheet with strikes on target to see the corollary and thereafter refine my zero as suggested by the corollary.
+1 Kraig
The most difficult zeros to refine for me are from the standing position. My method is the blind call and plot exercise where I dry fire and plot my call and then follow with live fire calling and plotting those shots too. After about 50 minutes of this I will overlay my call sheet with strikes on target to see the corollary and thereafter refine my zero as suggested by the corollary.
