Impact to the right at 600 yards plus

Do a tall target test. Place target at 100 yards and fire three shots. Then come up 10 minutes if MOA or pick a number like 3 Mils if in Mils. Aim at original dot. Repeat but coming up additional 10 or 3 again. If you scope is tracking true you will have a plumb or true vertical impact line. If there is any deviation from plumb there is your problem. Report back on this.
That is a good idea. Would need to make sure the target is completely level of course.
 
I came across this video that was pretty good . As many have suggested it is possible that my reticle is canted slightly. I have always just used a level on the receiver and then a level on the top of the turret. I never thought about the top of the turret possibly not being totally level with the reticle but it seems obvious that that could be a source of error. I don't have the tool he uses in the video, but leveling the receiver in a vise and then lining up on a plumb bob should do the same thing as others have suggested. I loaned out my levels though so will need to get back first.
 
How are you verifying velocity?
Nosler Accubond were (not sure if this is still the case) way off on their published BCs. How have you verified the BC?
Does this just show up as 8” @600, or do you see different results than expected/calculated at 400 and 500?
I would quit looking at spin drift as a suspect.
Measured with a chronograph. I have just been using the published BC. It seems to match the drop I am seeing out to 600 yards anyway. Have not shot further. It is not just showing up at 600. It shows to a correspondingly lesser degree at shorter distances as you would expect. I just was using 600 as the example.
 
Are the rifles being zeroed at 100 then being shot at 600 the same day?


Have you shot it outside of the lead sled to see what happens??


I've seen rifles do weird shit in a lead sled. But never gave them the time of day to figure out if it was user error or what. I just knew my rifle shot a hell of a lot better when it wasnt in that thing.
Yes, on the same day shot at 100 and was dead center and then at 600 and saw the difference. Saw the same result off of bipod.
 
Doubt it’s spin drift as that wouldn’t be that much at 600. However could account for some but not all.

It’s most likely the wind. As it would not take much change in direction or speed to cause this effect. And there’s no way to accurately measure wind across the range before shooting and rely on that for the duration of the session.

Wind constantly changes. That’s why having experience reading it is so important. Wind flags help a lot if your range has them out.

I’d expect even your ballistic app to be off that much. I run StrelokPro and have been happy with it

However in case I’m wrong here’s a simple math equation to do before a shot that will put you right back in the game
View attachment 7438650
Thanks! That cleared it right up ;) Should be able to just do that math in my head.
 
Do a tall target test. Place target at 100 yards and fire three shots. Then come up 10 minutes if MOA or pick a number like 3 Mils if in Mils. Aim at original dot. Repeat but coming up additional 10 or 3 again. If you scope is tracking true you will have a plumb or true vertical impact line. If there is any deviation from plumb there is your problem. Report back on this.
I static mount all my optics to test tracking - live firing is a poor method. I check plumb with a plumb bob.....I’m also not the OP with the issue, haha. I feel like this thread s really running off the rails, LOL.
 
I static mount all my optics to test tracking - live firing is a poor method. I check plumb with a plumb bob.....I’m also not the OP with the issue, haha. I feel like this thread s really running off the rails, LOL.
That sounds in line with what I am thinking with locking into the gun vice and checking reticle wth a plumb bob. Thanks for all of your input on this thread.
 
Since we started pulling all students scopes in our PR 1 class, we found a significant number are canted in their rings even a small amount. We see it because we use a level.

we used to only test scopes in PR 2 but now we test in PR 1 and at least 4 out of 12 are canTed in the rings, with another 4 or more canting due to a loose bipod during the shot string .

right handed shooters can’t right and pull right all the time, when you look 90% of new shooters put some noticeable amount of right hand influence into the shot. It’s bigger than any drift.

want to really see how bad you shoot, stop shooting groups at 100 and just try it at 200, I bet your average is 1.5% bigger than expected based off your 100 yard average. Got to 300 it will grow again.

SD is 1% of your elevation, so you need 10 miles to dial or observe .1 the rest is you. The 1 MOA at 1 second is fake, it’s a made up value.
 
Since we started pulling all students scopes in our PR 1 class, we found a significant number are canted in their rings even a small amount. We see it because we use a level.

we used to only test scopes in PR 2 but now we test in PR 1 and at least 4 out of 12 are canTed in the rings, with another 4 or more canting due to a loose bipod during the shot string .

right handed shooters can’t right and pull right all the time, when you look 90% of new shooters put some noticeable amount of right hand influence into the shot. It’s bigger than any drift.

want to really see how bad you shoot, stop shooting groups at 100 and just try it at 200, I bet your average is 1.5% bigger than expected based off your 100 yard average. Got to 300 it will grow again.

SD is 1% of your elevation, so you need 10 miles to dial or observe .1 the rest is you. The 1 MOA at 1 second is fake, it’s a made up value.
Thanks. That adds weight to needing to check the cant for sure. In terms of the group size growing, I haven't seen that. I have actually seen slightly smaller group sizes at the longer distances than would be predicted by the 100 yard group for whatever reason.
 
Measured with a chronograph. I have just been using the published BC. It seems to match the drop I am seeing out to 600 yards anyway. Have not shot further. It is not just showing up at 600. It shows to a correspondingly lesser degree at shorter distances as you would expect. I just was using 600 as the example.
I may have missed it above, are you dialing the wind at specific distance, or holding in the reticle?


Is you scope FFP of SFP if holding for wind?
You said the miss right scales with distance, which would seem to indicate your not dialing or holding for the wind, holding/dialing the wrong side, or a significant cant at 600 was others have said.

For me a 6mph full value wind is a 0.6mil and hold at 600y, and my scope is FFP so I don't need to worry about what magnification I'm on when holding.
 
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I may have missed it above, are you dialing the wind at specific distance, or holding in the reticle?

Is you scope FFP of SFP if holding for wind?

For me a 6mph full value wind is a 0.6mil and hold at 600y, and my scope is FFP so I don't need to worry about what magnification I'm on when holding.
Good question that I wasn't clear on, but I didn't compensate for the wind at all. Was looking to verify drift and just held dead on and then measured amount of drift compared to what was expected.
 
Good question that I wasn't clear on, but I didn't compensate for the wind at all. Was looking to verify drift and just held dead on and then measured amount of drift compared to what was expected.
Ok, bingo, first you need to stop thinking in linear measurements, inches of drift don't matter. You want the angular measurement mil or moa, and the ruler is right in front of you in your reticle.

If you were holding dead center and you measure 0.4mil right, you can go back into your ballistic solver and back that to the full value wind the bullet saw at that distance.

You said elevation was spot on so the MV and BC seem to be calibrated.
 
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Ok, bingo, first you need to stop thinking in linear measurements, inches of drift don't matter. You want the angular measurement mil or moa, and the ruler is right in front of you in your reticle.

If you were holding dead center and you measure 0.4mil right, you can go back into your ballistic solver and back that to the full value wind the bullet saw at that distance.

You said elevation was spot on so the MV and BC seem to be calibrated.
So for me, when I am shooting and not sure of the wind, and I hold center, I then use that as the real wind call.

For example if I thought there was no wind, held center at 500y and saw my miss was 1.0 mil right, I could go back into my app and increase the full value wind until I had a 1.0 mil hold. For my rifle that's 6mph full value wind.

Since I know my gun is a 6mph wind gun (lots of threads hear on mph wind method for wind hold), I could quickly see the 1.0 mil miss and know the real wind was 12mph and use this on my other targets.
 
So for me, when I am shooting and not sure of the wind, and I hold center, I then use that as the real wind call.

For example if I thought there was no wind, held center at 500y and saw my miss was 1.0 mil right, I could go back into my app and increase the full value wind until I had a 1.0 mil hold. For my rifle that's 6mph full value wind.

Since I know my gun is a 6mph wind gun (lots of threads hear on mph wind method for wind hold), I could quickly see the 1.0 mil miss and know the real wind was 12mph and use this on my other targets.
Hunting is my main application so I just want to make sure I can account for all the drift I am seeing on the first shot. Another thing I need to do is shoot on a perfectly calm day and see what I am seeing for drift. I just haven't had the chance yet.
 
I'm going to go with a stronger cross wind than where you measured, maybe a valley or wooded area pushes harder between you and the target?
I have no experience but am fair at math. Maybe when you took measurements and shot the wind changed speed?
 
I'm going to go with a stronger cross wind than where you measured, maybe a valley or wooded area pushes harder between you and the target?
I have no experience but am fair at math. Maybe when you took measurements and shot the wind changed speed?
Definitely possible, but would be odd that it increased for every shot and decreased on all of the handful of times we measured at points between us and target. It was a wheat field, but there were some rolling hills that could have changed wind currents a bit.
 
Hunting is my main application so I just want to make sure I can account for all the drift I am seeing on the first shot. Another thing I need to do is shoot on a perfectly calm day and see what I am seeing for drift. I just haven't had the chance yet.
Believe the bullet, if you have the elevation dialed in and your solver is accurately predicting drop, then trust it for the wind. If the bullet moved 0.4mil at 600y that's what it did. If the solver is acurately predicting the elevation drop, it is also accurately predicting the impact of the wind. You have no way to measure the wind all along the path, but you can trust the bullet did and it was a 0.4mil wind for your bullet out of your gun.
 
I may show my ignorance here in not know what is going on, but a buddy and I each have 7 mm rem mags. Mine is a savage, his a remington. Dialed in windage on both at 100 yards and shooting at 600 yards with both, we see 8 inches of drift to the right that we cannot account for. It was not wind related. Anybody know what is going on?
Do you have an anti Cant level on your scope?
 
I may show my ignorance here in not know what is going on, but a buddy and I each have 7 mm rem mags. Mine is a savage, his a remington. Dialed in windage on both at 100 yards and shooting at 600 yards with both, we see 8 inches of drift to the right that we cannot account for. It was not wind related. Anybody know what is going on?
 
Definitely possible, but would be odd that it increased for every shot and decreased on all of the handful of times we measured at points between us and target. It was a wheat field, but there were some rolling hills that could have changed wind currents a bit.
As you increase distance the wind affect increases... its not a fixed distance offset....
 
So you’re off 0.4 mils right. Hold 0.4 mils left. To quote Frank: “Use the ruler 3” in front of your nose.”
Do you have a source to share for understanding mils? I am trying to wrap my head around it still, but one source said that .1 mil is .36" at 100 yards. This is assuming that the scope adjusts in 1/10th increments. I am just trying to figure this out.

Thank you

Goat
 


Ryan Cleckner former ArmySniper does a pretty thorough job of explaining mils in this YouTube video.

But if you’re still trying to convert mils to inches and then from inches back to mils you’re missing the real value of your reticle.

Spot your miss, note the number of mils (Using your reticle subtensions) you missed by, adjust your hold by that number, send it.
 
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No you need to make sure impacrs rise and drop straight up and down..... a string or level will work
That is what I do. I take a long piece of newsprint and staple it to a 4x8 piece of wafer board that I have mounted so the 8' is the vertical at 300 yards. I hang a plumb line, make a couple marks, then use a chalk line to snap a line. I draw an aiming point using a compass and color it in with a sharpie. Then I go shoot groups. I shoot a group of 3, then dial some elevation and aim at the same point, shoot another group and repeat until I either run out of target or see a problem. If your scope vertical is not perfectly plumb through the bore, it will show up. It's amazing (to me) just how little off can make such a huge difference at some distance. When I do make a little twist, I first use a 0.5mm lead pencil to make an index mark on scope and usually the rear ring. I use up some ammo but I don't mind shooting.
Charley Robertson of Scorehi in Albuquerque has a good read on how he sets up a scope and he doesn't charge all that much to do so, especially with the current cost of components or loaded ammo.