when a scope has moa adjustments is that shooters moa (1" @ 100yds) or real moa not that there is enough diffrence to matter (just less than 1" @ 2000 yds) i was just curous
Rifle Scopes moa adjustments
- Thread starter 42769vette
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Re: moa adjustments
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">when a scope has moa adjustments is that shooters moa (1" @ 100yds) or real moa not that there is enough diffrence to matter (just less than 1" @ 2000 yds) i was just curous</div></div>
There is no generic answer to that question. You'll have to test the specific scope.
For example, I have tested many Leupold 6.5-20X50M1 scopes, which are marked as having 1/4-MOA adjustments. All those I tested actually have adjustments nearer 1 inch per hundred yards (IPHY) for 4 clicks than to 1.047.
In addition, some manufactureres - notably U.S. Optics - deliberately make scopes which adjust in IPHY as well as having IPHY reticles.
I test every new scope to find out what the reticle and adjustments really are. See:
Optically Checking Rifle Scopes
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">when a scope has moa adjustments is that shooters moa (1" @ 100yds) or real moa not that there is enough diffrence to matter (just less than 1" @ 2000 yds) i was just curous</div></div>
There is no generic answer to that question. You'll have to test the specific scope.
For example, I have tested many Leupold 6.5-20X50M1 scopes, which are marked as having 1/4-MOA adjustments. All those I tested actually have adjustments nearer 1 inch per hundred yards (IPHY) for 4 clicks than to 1.047.
In addition, some manufactureres - notably U.S. Optics - deliberately make scopes which adjust in IPHY as well as having IPHY reticles.
I test every new scope to find out what the reticle and adjustments really are. See:
Optically Checking Rifle Scopes
Re: moa adjustments
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 42769vette</div><div class="ubbcode-body">when a scope has moa adjustments is that shooters moa (1" @ 100yds) or real moa not that there is enough diffrence to matter (just less than 1" @ 2000 yds) i was just curous</div></div>
Knowing the value does matter when re-zeroing from SR to LR.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 42769vette</div><div class="ubbcode-body">when a scope has moa adjustments is that shooters moa (1" @ 100yds) or real moa not that there is enough diffrence to matter (just less than 1" @ 2000 yds) i was just curous</div></div>
Knowing the value does matter when re-zeroing from SR to LR.
Re: moa adjustments
Yes. The difference in point of impact between IPHY and MOA adjustments at 1000 yards with a typical .308 load is 20 inches - which is a big miss on most targets if you think you have one but actually have the other.
Yes. The difference in point of impact between IPHY and MOA adjustments at 1000 yards with a typical .308 load is 20 inches - which is a big miss on most targets if you think you have one but actually have the other.
Re: moa adjustments
If the scope says .25 MOA on the turret, it is true MOA. If it says 1/4 inch, it is shooters MOA. If you are shooting long range, you will see a difference. If you get out past say 600-700 yds, run your calculations to estimate distance. Depending on method you are using, the differnce may be 20+ yds. If you find the calculcations, you will see that true MOA is multiplied by 100 to estimate range, and shooters MOA is multiplied by 95.5. I don't remember where I found those equations at, put you could probably just run a search and find it.
If the scope says .25 MOA on the turret, it is true MOA. If it says 1/4 inch, it is shooters MOA. If you are shooting long range, you will see a difference. If you get out past say 600-700 yds, run your calculations to estimate distance. Depending on method you are using, the differnce may be 20+ yds. If you find the calculcations, you will see that true MOA is multiplied by 100 to estimate range, and shooters MOA is multiplied by 95.5. I don't remember where I found those equations at, put you could probably just run a search and find it.
Re: moa adjustments
42769vette,
The difference between MOA and Shooters MOA is +0.047" per inch. If you adjust your scope to hit a target @ 1000 yds with a 308 winchester, you will need to compensate for around 390 inches of drop. 390 inches x 0.047" = 18.33 inches of error or around 4.7%.
If you thought your scope was adjusting in IPHY instead of MOA or visa versa, that's how much your error will be @1000 yds. If you think the the error is only 2" at 2000 yds, you will need to sharpen your calculator. If you were using a laser you would be correct. If your using a bullet, the small 0.047 inches of error multiplies by the total inches of drop you have to compensate for.
Bob
42769vette,
The difference between MOA and Shooters MOA is +0.047" per inch. If you adjust your scope to hit a target @ 1000 yds with a 308 winchester, you will need to compensate for around 390 inches of drop. 390 inches x 0.047" = 18.33 inches of error or around 4.7%.
If you thought your scope was adjusting in IPHY instead of MOA or visa versa, that's how much your error will be @1000 yds. If you think the the error is only 2" at 2000 yds, you will need to sharpen your calculator. If you were using a laser you would be correct. If your using a bullet, the small 0.047 inches of error multiplies by the total inches of drop you have to compensate for.
Bob
Re: moa adjustments
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">If the scope says .25 MOA on the turret, it is true MOA. If it says 1/4 inch, it is shooters MOA.</div></div>
I'm afraid that turns out not to be the case. They are often marked incorrectly, as most shooters don't know the difference between MOA and IPHY.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">If the scope says .25 MOA on the turret, it is true MOA. If it says 1/4 inch, it is shooters MOA.</div></div>
I'm afraid that turns out not to be the case. They are often marked incorrectly, as most shooters don't know the difference between MOA and IPHY.
Re: moa adjustments
Hopefully you'd be setting up a drop chart for your load though, so really it doesnt matter all that much. I find calculated ballistics to have more error than the difference between shooters MOA and IPHY anyway.
Then once youre down to adjusting for say a 5" miss, the difference between the two is totally negligible at 1000yds anyway.
Hopefully you'd be setting up a drop chart for your load though, so really it doesnt matter all that much. I find calculated ballistics to have more error than the difference between shooters MOA and IPHY anyway.
Then once youre down to adjusting for say a 5" miss, the difference between the two is totally negligible at 1000yds anyway.
Re: moa adjustments
jonaddis,
Perhaps I'm not reading your post right, but how is a drop chart going to know that your scope adjusts in IPHY instead of MOA or visa versa, like you assumed? So a near 5% error is negligible? How are you going to get to a 5" miss if your adjustments are off 19" @ 1000 from what you thought?
And you find the error in JBM Calculations for example to be off more than 20" @ 1000 yds? Even if you chrono your load, and use the Litz corrected BC's? Could you explain that a little more please?
Also IPHY and Shooters MOA is the same thing, ie no difference. However, I think you meant to say the difference between True MOA and IPHY, or not?
But perhaps I'm just not grasping the thrust of your post.
Thanks,
Bob
jonaddis,
Perhaps I'm not reading your post right, but how is a drop chart going to know that your scope adjusts in IPHY instead of MOA or visa versa, like you assumed? So a near 5% error is negligible? How are you going to get to a 5" miss if your adjustments are off 19" @ 1000 from what you thought?
And you find the error in JBM Calculations for example to be off more than 20" @ 1000 yds? Even if you chrono your load, and use the Litz corrected BC's? Could you explain that a little more please?
Also IPHY and Shooters MOA is the same thing, ie no difference. However, I think you meant to say the difference between True MOA and IPHY, or not?
But perhaps I'm just not grasping the thrust of your post.
Thanks,
Bob
Re: moa adjustments
i guess i didnt think the whole 1" at 2000 yards thing out completely before posting. thanks for straighting me out.
i guess i didnt think the whole 1" at 2000 yards thing out completely before posting. thanks for straighting me out.
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