Bullet drift no wind

cassieaaron

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Feb 5, 2009
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I need help. I consider myself a decent shooter but I'm having an issue with drift. I am shooting a 308 remington 700 in a bedded hs stock. And 6-24 vortex scope. Gun is more than capable of sub moa groups. But at 500 yards getting 8" of drift to the right. That's a 1.75 mil adjustment at 500 yards in drift with 0 wind. I have shot many times and not had this much bullet drift at 500. Iwas told by several that this can be caused by canting and or trigger pull. So I had 2 different shooter test today and all shot same to the right. If fact all shots combined maintained a 4" group at 500 with 3 different shooters. My group was 1.2" at this range. I can't figure out why i have so much drift?
 

cassieaaron

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Feb 5, 2009
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also I tested scope level tonight tested on levels. I shot at 100 yds. Made a 30 mil adjustment up and shot again at 100 yds. It tracked perfectly up. No drift to the right that would indicate improper alignment. So does anyone have any suggestions or ideas?
 

338Rocket

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Edit, posted at the same time.

Did you try dialing for 500 as well as holding over? See if POI is the same.
 

cassieaaron

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Feb 5, 2009
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yes that is the exact tracking test i performed. scope tracks perfectly and 0 movement.
i have not tried shoot at 500 using the mil rads instead of tracking. i can try that as well, however i believe it will confirm what this test is already confirming that the scope is tracking properly.
will keep you posted.
 

lancetkenyon

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First, 1.75 MIL is 31.5" @ 500 yards, no 8". So am going out on a limb and thinking you mean 1.75 MOA, which is 8.7" @ 500 yards.

So without knowing your bullet weight and velocity or barrel twist rate, and assuming right hand twist barrel, I can see 1-2"of spin drift at 500 yards being possible.

Are you sure you are dead center for windage @ 100 yards? Not maybe 1/4" right? Which would add another 1.25" right @ 500.

Do you have an anti-cant device (level) on your scope? Even a degree or three can add a right POI on target. And if you do, is your reticle plumb and leveled with you rifle?

Are you sure it was an absolute 0 wind? Even a 2mph breeze could push another 3" or more @ 500.
 

cassieaaron

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Feb 5, 2009
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You are correct I meant 1.75 moa. Ido not have a anti can't decide. I have one on order. However I have checked the level on scope and tested the tracking. But as far as canting I could understand 2-3" but 8? I should also mention I have consistent shot this group over several different trips. I also am shooting excellent groups 1-2" consistently at 500. I have learned to just make the adjustment and can hit dead on every time. I am just trying to get my mind around this phenomenon
 

WildRose

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You are correct I meant 1.75 moa. Ido not have a anti can't decide. I have one on order. However I have checked the level on scope and tested the tracking. But as far as canting I could understand 2-3" but 8? I should also mention I have consistent shot this group over several different trips. I also am shooting excellent groups 1-2" consistently at 500. I have learned to just make the adjustment and can hit dead on every time. I am just trying to get my mind around this phenomenon
Out beyond about 400yds not having a scope level can really cause you problems.

Start there and then see where it takes you.
 

Jim5351

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Nov 4, 2008
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It sounds like your scope might not be aligned with your barrel. What base and rings are on your rifle? I have had that problem with the scope out of alignment myself.
 
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