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Location: North Louisiana
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Figuring MOA
fuzzybear wrote:
Very nice group. Can you get three to cloverleaf?
Shooting a rifle that has been set up for extreme accuracy is quite the challenge. When you can get all three to touch it's a thrill.
What powder are you using? I have my best loads with slower Hodgdon and Reloder. My 270wsm really likes H1000 with the 140gr accubond.

One of the LR shooters that I know said he was going to experiment with the Nosler Accubonds that they were getting good results. I haven't seen him for a while. So, I have no idea what the results were. At that time Nosler had them in 270, 7mm and 30 cal. This guy goes as far as spinning his bullets to make sure they are perfectly balanced and the ogive is the same.

fuzzbar

"This guy goes as far as spinning his bullets to make sure they are perfectly balanced and the ogive is the same."

Boy oh boy!! I wonder if he can spin 'em at 200,000 rpm to check 'em?? If he spent that time shootin and learning to read the wind.....he might be accomplishing something worthwhile! Maybe he weighs his primers also!

My arse!! Brick Wall,) neener!

CVC
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Figuring MOA

Let's see if I've got this figured out. My rifle is zeroed at 200 yards. I put the numbers into the Hornady calculator and it tells me that I will be 47.5 inches low at 500. So, at 500 one click on my scope = 1/4 inch at 100 X 5 = 1.25.

47.5/1.25 = 38 clicks on the scope - right?

The Hornady calculator says come up 9.1 MOA at 500 so another way to figure it would be 4 X 9.1 = 36 or 37 clicks on the scope adjustment?

180 gr., .506 B.C. http://www.hornady.com

Range (yards) Muzzle 50 100 200 300 400 500
Velocity (fps) 2670 2588 2508 2352 2201 2056 1917
Energy (ft.-lb.) 2849 2678 2514 2211 1937 1690 1469
Trajectory (200 yd. zero) -1.5 0.9 2.0 0.0 -8.3 -23.8 -47.5
Come Up in MOA -1.5 -1.7 -1.9 0.0 2.6 5.7 9.1

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Figuring MOA

At 500yds Hoenady has you 59" low. Each click will move the bullet 1.25".

1/4 @ 100yds = 1/4 x 5 @ 500yds = 1.25" adjust at 500yds per click.

59" low divided by 1.25" per click = 47.2 clicks and you'll be 1/4" low. 48 clicks will put you 3/4" high. Think I got that right. If it's wrong, I'm sure CG will e around. He's better at that than I am.

CVC
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Figuring MOA

Ok - I see where we got different numbers. I plugged in a 300 zero when I should have used a 200 and you're using a 100 zero.

But I think we're calculating things the same way: divide the drop by 1.25 to get the number of clicks to adjust the scope.

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Figuring MOA

Forget the zero. What your doing is raising the strike of the bullet "X" number of inches at "X" number of yards. All the zero will do is change the path of the bullet.

The bullet will have dropped less at 500yds with a 300 yds zero than with a 100 yd zero. But then with the 100yd zero, the bullet will not rise as far above line of sight at any point as it will with a 300 yd zero.

That is why some of us use the Max Point Blank Range (MPBR) method of zeroing in a rifle. It makes the most of the trajectory the cartridge and bullet selected has to offer before you have to start adjusting for drop. It also controls how much the bullet will rise above the line of sight.

If this sounds confusing, draw a straight line on a paper, that is line of sight as seen thru the scope. Now draw an arch starting at one end, rising above the line of sight then passing thru it somewhere along the way. Where it passes thru is zero. Call that 300yds. At 500yds it will continue to fall, even more rappidly as velocity falls off. To bring the bullet up to "zero" at 500 yds, you have to raise the sights to compensate for the drop between 300yds and 500yds, forget everything befor 300yds. Unless you have zeroed at say 100yds. The you compensate for the drop between 100yds and 500yds.

If you scope moves the strike of the bullet 1/4" @ 100yds, multiply 1/4" times the number of yards you want and that's how far the click will move the strike at the new range. Devide the drop at that range by the movement per click at that range and you have number of clicks to move it.

I hope I got this all right. Chester Golf taught me this. When it finally clicked with me, I felt stupid! Yes

CVC
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Figuring MOA

Thanks

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Location: Mobile County, Alabama
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Figuring MOA

1moa equals the following:

1 moa at 100 yards is 1 inch, 2 moa at 100 yards is 2 inches, 3 moa at 100 yards is 3 inches and so on.

1 moa at 200 yards is 2 inches, 2 at 200 yards is 4 inches, 3 moa at 200 yards is 6 inches, etc.

1 moa at 300 yards is 3 inches, 2 moa at 300 yards 6 inches, 3 moa at 300 yards is 9 inches, etc.

See a trend? Yep, it's easy. Big smile

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