Shot from distances of 200 to 800 yards today. At 200 where the rifle is zeroed I was hitting dead center. Elevation was spot on but as I progressed further out the rounds kept landing to the right. At 800 yards it was pretty significant. I am shooting a bolt action rifle, left handed in prone position. I don't believe it's the equipment in fact I'm sure it's something I'm doing. A little help on how to correct this would be appreciated. Thank you.
- Thread starter Russell3812
- Start date
Re: Technique
How fast of a twist is your barrel? Men's 1/10 and I have about .4 moa spin drift at 800. Out to 5 it is almost neglible. After that I start correcting for it.
How fast of a twist is your barrel? Men's 1/10 and I have about .4 moa spin drift at 800. Out to 5 it is almost neglible. After that I start correcting for it.
Re: Technique
twist is 1/10. I am certain the scope is level but will also try box test if it helps.
twist is 1/10. I am certain the scope is level but will also try box test if it helps.
Re: Technique
Usually when we find someone with that problem they've never tracked the scope thru it's total elevation needed from starting to final elevation changes needed. That is where I'd start checking for a solution at a closer distance such as 75 to 100 yards where Mother Nature isn't much of a factor. What you are calling a "box test" isn't going to tell if your scope is tracking perfectly true up a line but more if a scope will make various windage and elevation changes and come back to it's original setting and also move in the correct amount with each click.
If that all works out then you can move on to things involving shooter input affecting it. Thinking your scope is level and not taking the time to shoot a few rounds up a verticle line and see the proof is like only doing half the job. Not saying wind drift don't exist but I've yet to have to worry about inputting it for any target we shoot out to 1000 yards even with our slower velocity LR pistols.
Topstrap
Usually when we find someone with that problem they've never tracked the scope thru it's total elevation needed from starting to final elevation changes needed. That is where I'd start checking for a solution at a closer distance such as 75 to 100 yards where Mother Nature isn't much of a factor. What you are calling a "box test" isn't going to tell if your scope is tracking perfectly true up a line but more if a scope will make various windage and elevation changes and come back to it's original setting and also move in the correct amount with each click.
If that all works out then you can move on to things involving shooter input affecting it. Thinking your scope is level and not taking the time to shoot a few rounds up a verticle line and see the proof is like only doing half the job. Not saying wind drift don't exist but I've yet to have to worry about inputting it for any target we shoot out to 1000 yards even with our slower velocity LR pistols.
Topstrap
Re: Technique
If windage is indeed being taken along for the ride it can be checked. Just shoot at 200 yards with the 800 yard zero and see if shots go to the right.
If windage is indeed being taken along for the ride it can be checked. Just shoot at 200 yards with the 800 yard zero and see if shots go to the right.
Re: Technique
Scope cant?
Rifle buttplate screws parallel to a plumb line, rifle is level.
Scope horizontal wire parallel to siding on nearby building, scope is level.
If you have both, your scope is not canted.
Scope cant?
Rifle buttplate screws parallel to a plumb line, rifle is level.
Scope horizontal wire parallel to siding on nearby building, scope is level.
If you have both, your scope is not canted.
Re: Technique
I would agree that it is spin drift. At 1000 yds with no wind i have .2 mils left dialed or about 7.2 inches.
I would agree that it is spin drift. At 1000 yds with no wind i have .2 mils left dialed or about 7.2 inches.
Re: Technique
I would say that all things mentioned can be a factor in your issue,
want to eleminate all variables, check your scope level, put a level on your gun and level the receiver every shot, if your using a crap factory triger upgrade it, a 4lb triger take much longer for "me" to learn to shoot well. test your scope if you have a clamping style rest of some sorts and run your elevation turet up and see if it tracks up perfectly.
with all that said, tell us a little more about your gun and ammo. scope triger, barrel and twist... more info would help us nail it down to a specific
but theres nothing wron with any of these above mentioned ideals, triger control is huge.
JW
I would say that all things mentioned can be a factor in your issue,
want to eleminate all variables, check your scope level, put a level on your gun and level the receiver every shot, if your using a crap factory triger upgrade it, a 4lb triger take much longer for "me" to learn to shoot well. test your scope if you have a clamping style rest of some sorts and run your elevation turet up and see if it tracks up perfectly.
with all that said, tell us a little more about your gun and ammo. scope triger, barrel and twist... more info would help us nail it down to a specific
but theres nothing wron with any of these above mentioned ideals, triger control is huge.
JW
Re: Technique
Thank you all for your comments. Earlier I mentioned that I believe its myself and not the scope because I went through painstaking methods to install it properly. I bought the wheeler scope mounting kit. Used both levels in the kit to ensure the rifle and scope were level. I also installed a Vortex anti-cant device or bubble level on scope to make sure no cant exists when I shoot. The base is from ECW 20MOA and the rings are Seekins Precision. My scope is a Sightron SIII 6x24.The rifle is a Savage 308 1-10 twist and the trigger is the factory accutrigger. I'm not an expert by any means but I am very hesitant to blame it on the equipment. I really have taken my time setting it up and think anything at this point is shooter error. The day I noticed this there was no wind present. But to eliminate any doubt about it being the equipment I am ready to do the "box test" next time at the range. This was the second time for me shooting out to these distances. I had never turned the elevation turret past 2 MOA prior to this and had dialed in over 30 MOA which was two full revolutions of the dial. I don't have the opportunity to shoot to such distances at a regular basis and for the past year only had 200 yards at most. I've become pretty proficient at shooting that distance but now that I pushed further out I observed the problem I mentioned above. If it's my "trigger control" I am more than ready to accept it and work on it. Just looking to eliminate all possiblities and humbly ask for direction. Thank you again.
Thank you all for your comments. Earlier I mentioned that I believe its myself and not the scope because I went through painstaking methods to install it properly. I bought the wheeler scope mounting kit. Used both levels in the kit to ensure the rifle and scope were level. I also installed a Vortex anti-cant device or bubble level on scope to make sure no cant exists when I shoot. The base is from ECW 20MOA and the rings are Seekins Precision. My scope is a Sightron SIII 6x24.The rifle is a Savage 308 1-10 twist and the trigger is the factory accutrigger. I'm not an expert by any means but I am very hesitant to blame it on the equipment. I really have taken my time setting it up and think anything at this point is shooter error. The day I noticed this there was no wind present. But to eliminate any doubt about it being the equipment I am ready to do the "box test" next time at the range. This was the second time for me shooting out to these distances. I had never turned the elevation turret past 2 MOA prior to this and had dialed in over 30 MOA which was two full revolutions of the dial. I don't have the opportunity to shoot to such distances at a regular basis and for the past year only had 200 yards at most. I've become pretty proficient at shooting that distance but now that I pushed further out I observed the problem I mentioned above. If it's my "trigger control" I am more than ready to accept it and work on it. Just looking to eliminate all possiblities and humbly ask for direction. Thank you again.
Re: Technique
Your scope can be exactly according to approved mounting specs and still be faulty, giving symptoms that mimic cant.
Swap scopes, do the levelling, and see if the problem persists.
Whenever an anomoly gives a consistent effect, that usually rules out a human origin. Humans just aren't capable of screwing up in an infallibly consistent manner.
Greg
Your scope can be exactly according to approved mounting specs and still be faulty, giving symptoms that mimic cant.
Swap scopes, do the levelling, and see if the problem persists.
Whenever an anomoly gives a consistent effect, that usually rules out a human origin. Humans just aren't capable of screwing up in an infallibly consistent manner.
Greg
Re: Technique
Go back to the range and first test to see if you are getting the same results. Your suggestion that there was no wind made me curious. Sometimes a 1 or 2 mph wind would be hard to detect unless it were moving smoke. Of course this would get you the sort of results you got. I don't think your result is parallax error but if your scope was just slightly out of focus I suppose it could. If your problem is indeed trigger control I wonder why you did not see it at 200 yards. That's to say if you are jerking, it must be a pretty consistent jerk thus masking error at the short line. At any rate you have an interesting problem. I still think the reticle is not level and you are taking a small amount of windage along for the ride. It is easy to test for that.
Go back to the range and first test to see if you are getting the same results. Your suggestion that there was no wind made me curious. Sometimes a 1 or 2 mph wind would be hard to detect unless it were moving smoke. Of course this would get you the sort of results you got. I don't think your result is parallax error but if your scope was just slightly out of focus I suppose it could. If your problem is indeed trigger control I wonder why you did not see it at 200 yards. That's to say if you are jerking, it must be a pretty consistent jerk thus masking error at the short line. At any rate you have an interesting problem. I still think the reticle is not level and you are taking a small amount of windage along for the ride. It is easy to test for that.
Re: Technique
As mentioned above, there are several things that could account for the right shift in POI at greater distance. Some of the possibilities given would be equipment-related, some shooter-related. In order to better diagnose the underlying issue(s), it would be helpful to have more information. You mentioned that the shift in POI to the right was "significant". Knowing exactly how much the POI shifted right from POA would be informative. Also, how did the pattern of your groups at longer distance compare to those at 200 yd? Same, more vertical dispersion, more horizontal dispersion? I'm inclined to agree with Sterling in that if you're jerking the trigger, it must be very consistent; otherwise you should be able to see it, even at 200 yd. Spin drift from a 10-twist barrel is a possibility, but it should be relatively small at 800 yd (~0.5 MOA or less). So knowing exactly how far right your were hitting at 800 yd might be helpful to rule out at least one possibility.
Another possibility mentioned was scope cant. This topic was discussed in detail in the following thread: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2189771#Post2189771. Although it sounds as though you were very careful mounting your optic, it's still a possibility given the description of your problem. Bottom line is that eliminating as many of the possible sources for the right shift as you can will be helpful in narrowing down the real culprit. If it ends up being you, so be it, you'll know what to work on to fix the issue. However, if there <span style="font-style: italic">is</span> an equipment issue, you could spend a lot of time and ammo working on your trigger control without rectifying the issue. Not that that would be a wasted effort, in the long run many could benefit from those types of exercises. Anyhow, good luck with it.
As mentioned above, there are several things that could account for the right shift in POI at greater distance. Some of the possibilities given would be equipment-related, some shooter-related. In order to better diagnose the underlying issue(s), it would be helpful to have more information. You mentioned that the shift in POI to the right was "significant". Knowing exactly how much the POI shifted right from POA would be informative. Also, how did the pattern of your groups at longer distance compare to those at 200 yd? Same, more vertical dispersion, more horizontal dispersion? I'm inclined to agree with Sterling in that if you're jerking the trigger, it must be very consistent; otherwise you should be able to see it, even at 200 yd. Spin drift from a 10-twist barrel is a possibility, but it should be relatively small at 800 yd (~0.5 MOA or less). So knowing exactly how far right your were hitting at 800 yd might be helpful to rule out at least one possibility.
Another possibility mentioned was scope cant. This topic was discussed in detail in the following thread: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2189771#Post2189771. Although it sounds as though you were very careful mounting your optic, it's still a possibility given the description of your problem. Bottom line is that eliminating as many of the possible sources for the right shift as you can will be helpful in narrowing down the real culprit. If it ends up being you, so be it, you'll know what to work on to fix the issue. However, if there <span style="font-style: italic">is</span> an equipment issue, you could spend a lot of time and ammo working on your trigger control without rectifying the issue. Not that that would be a wasted effort, in the long run many could benefit from those types of exercises. Anyhow, good luck with it.
Re: Technique
I have the wheeler level kit. I've never been able to get my scopes level with it. I have much more luck with the feeler gauge method.
You don't actually need to do a full box test for this. Get a big piece of cardboard. Use a long level to draw a vertical line on the cardboard. Put an aiming point at the bottom and shoot at it, dialing up between shots while keeping the reticle exactly on the vertical line on the cardboard. Use this to verify the "click" value for your scope at the same time. Try to go at least 36 inches up. More is better if your scope will do it. If the shots drift off to the side of the line, the scope is not level.
I have the wheeler level kit. I've never been able to get my scopes level with it. I have much more luck with the feeler gauge method.
You don't actually need to do a full box test for this. Get a big piece of cardboard. Use a long level to draw a vertical line on the cardboard. Put an aiming point at the bottom and shoot at it, dialing up between shots while keeping the reticle exactly on the vertical line on the cardboard. Use this to verify the "click" value for your scope at the same time. Try to go at least 36 inches up. More is better if your scope will do it. If the shots drift off to the side of the line, the scope is not level.
Re: Technique
Lots of good stuff here. I will try all of this and post an update. Appreciate your help.
Lots of good stuff here. I will try all of this and post an update. Appreciate your help.
Re: Technique
Cant has a negative effect on elevation, the hit will not only be off to the side but low too.
Errors in cant have a dual effect, sideways and with a loss in elevation.
Cant has a negative effect on elevation, the hit will not only be off to the side but low too.
Errors in cant have a dual effect, sideways and with a loss in elevation.
Re: Technique
Agree with cant causing elevation as well as windage being off if the rifle is canted but I think he'd see it only if he has pre-existing settings to go by. If he's getting settings or shooting for the first time with that gun/load/setup then he's just cranking in elevation to hit the target and it's moving off to one side the farther out he shoots. He wouldn't know that it's also shooting lower and also to the side based on previous correct elevation settings.
I could be wrong but seems a quick verticle tracking test is still a good place to start at a close distance then move on to technique.
Topstrap
Agree with cant causing elevation as well as windage being off if the rifle is canted but I think he'd see it only if he has pre-existing settings to go by. If he's getting settings or shooting for the first time with that gun/load/setup then he's just cranking in elevation to hit the target and it's moving off to one side the farther out he shoots. He wouldn't know that it's also shooting lower and also to the side based on previous correct elevation settings.
I could be wrong but seems a quick verticle tracking test is still a good place to start at a close distance then move on to technique.
Topstrap
Re: Technique
For those that did not see (or have yet to click on the above posted thread).
It makes sense that cant should affect elevation, however, in the above referenced experiment it did not...
I found this thread a few days ago... Scope Cant Optical Illusion. The OP observed an optical illusion where a level scope appears canted left. I observed the same thing on my scope and have confirmed it with both a scope level and a plumb bob. When the reticle is level according to the plumb bob, the bubble level also indicates level. However, if I do not have a vertical or horizontal line for reference, the reticle appears canted left when the bubble level indicates level. (Over)Correcting for this illusion would cause shots to be pushed left due to an inadvertent cant to the right.
While I do not know that this is the cause, it is a formal possibility, especially at range.
For those that did not see (or have yet to click on the above posted thread).
It makes sense that cant should affect elevation, however, in the above referenced experiment it did not...
I found this thread a few days ago... Scope Cant Optical Illusion. The OP observed an optical illusion where a level scope appears canted left. I observed the same thing on my scope and have confirmed it with both a scope level and a plumb bob. When the reticle is level according to the plumb bob, the bubble level also indicates level. However, if I do not have a vertical or horizontal line for reference, the reticle appears canted left when the bubble level indicates level. (Over)Correcting for this illusion would cause shots to be pushed left due to an inadvertent cant to the right.
While I do not know that this is the cause, it is a formal possibility, especially at range.
Re: Technique
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Russell3812</div><div class="ubbcode-body">Shot from distances of 200 to 800 yards today. At 200 where the rifle is zeroed I was hitting dead center. Elevation was spot on but as I progressed further out the rounds kept landing to the right. </div></div>It's not spin drift. It might be trigger. It's probably not cant. Box your scope and rule that out first.
I have the same problem when switching from my AICS .308s to my McMillan stocked .308: No vertical POI shift whatsoever; but a dead-straight horizontal .2R shift at 300m, .3R shift at 500m, and so on. I would blame it on my own bad shooting except that it's a predicable shift while still giving consistent and repeatable .2 MOA 3-shot groups at 300m and .4 MOA 5-shot groups at 500m. To confirm, when I dial left adjustments and shoot reference groups at 100m I am exactly the same number of adjustments left of POA that I added for distance. And as yet I have no idea what's going on.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Russell3812</div><div class="ubbcode-body">Shot from distances of 200 to 800 yards today. At 200 where the rifle is zeroed I was hitting dead center. Elevation was spot on but as I progressed further out the rounds kept landing to the right. </div></div>It's not spin drift. It might be trigger. It's probably not cant. Box your scope and rule that out first.
I have the same problem when switching from my AICS .308s to my McMillan stocked .308: No vertical POI shift whatsoever; but a dead-straight horizontal .2R shift at 300m, .3R shift at 500m, and so on. I would blame it on my own bad shooting except that it's a predicable shift while still giving consistent and repeatable .2 MOA 3-shot groups at 300m and .4 MOA 5-shot groups at 500m. To confirm, when I dial left adjustments and shoot reference groups at 100m I am exactly the same number of adjustments left of POA that I added for distance. And as yet I have no idea what's going on.
Re: Technique
Caliber? Velocity?
I didn't see the OP state that there was no wind (there's rarely such a thing, esp. with a 308), or quantify "how far right" the impacts were. Were they consistent?
I'm going for the easiest possible answer here - It's just wind.
All the other more technical issues still could be true, but we may have a tiger chasing its tail.
--Fargo007
Caliber? Velocity?
I didn't see the OP state that there was no wind (there's rarely such a thing, esp. with a 308), or quantify "how far right" the impacts were. Were they consistent?
I'm going for the easiest possible answer here - It's just wind.
All the other more technical issues still could be true, but we may have a tiger chasing its tail.
--Fargo007
Re: Technique
It's been awhile since my original post. I had the chance yesterday to go out to my local range and do a vertical line test. I placed my target at 100 yards. After establishing my 100 yard zero I fired shots from the bottom of the target up dialing elevation in 100 yard increments up to 700. For the most part the shots tracked straight up the line. I say for the most part because it was more difficult than I thought to dial in all this elevation and fit the shots on my 12" target. But the results I got from this test proved to me that the scope is tracking as it should straight up and down.
As mentioned earlier, the day I observed the shots moving right as distance increased was the second time I had ever had the opportunity to actually engage targets at that type of distance.
A year ago when I purchased this rifle and started shooting I had a 100 yard range. My first time out produced 5" groups. I practiced, read some stuff, bought better ammunition, started reloading eventually and got those groups under an inch. I joined a range at the beginning of this year that had a 200 yard lane. Not as bad as my original 5" groups but looked a lot worse than the 100 yard ones. I practiced, read some more stuff, and now I have those under an inch at 200.
With respect to the original post I believe that the shot placement going right is a result of my inexperience shooting out to these distances. I need to get some more range time in and practice my shooting. Every milestone I've reached so far has presented new challenges and I look forward to tackling this one knowing my equipment is set up correctly.
As always I got a lot of good information from your posts. Thank you for your help.
It's been awhile since my original post. I had the chance yesterday to go out to my local range and do a vertical line test. I placed my target at 100 yards. After establishing my 100 yard zero I fired shots from the bottom of the target up dialing elevation in 100 yard increments up to 700. For the most part the shots tracked straight up the line. I say for the most part because it was more difficult than I thought to dial in all this elevation and fit the shots on my 12" target. But the results I got from this test proved to me that the scope is tracking as it should straight up and down.
As mentioned earlier, the day I observed the shots moving right as distance increased was the second time I had ever had the opportunity to actually engage targets at that type of distance.
A year ago when I purchased this rifle and started shooting I had a 100 yard range. My first time out produced 5" groups. I practiced, read some stuff, bought better ammunition, started reloading eventually and got those groups under an inch. I joined a range at the beginning of this year that had a 200 yard lane. Not as bad as my original 5" groups but looked a lot worse than the 100 yard ones. I practiced, read some more stuff, and now I have those under an inch at 200.
With respect to the original post I believe that the shot placement going right is a result of my inexperience shooting out to these distances. I need to get some more range time in and practice my shooting. Every milestone I've reached so far has presented new challenges and I look forward to tackling this one knowing my equipment is set up correctly.
As always I got a lot of good information from your posts. Thank you for your help.
Re: Technique
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Russell3812</div><div class="ubbcode-body">It's been awhile since my original post. I had the chance yesterday to go out to my local range and do a vertical line test. I placed my target at 100 yards. After establishing my 100 yard zero I fired shots from the bottom of the target up dialing elevation in 100 yard increments up to 700. For the most part the shots tracked straight up the line. I say for the most part because it was more difficult than I thought to dial in all this elevation and fit the shots on my 12" target. But the results I got from this test proved to me that the scope is tracking as it should straight up and down. </div></div>
I'm still not sure you did that verticle tracking test correctly after reading your response. You can't put that much elevation onto a 12" target and still be seeing your hits if you are still aiming at the same mark on your target you started with at your 100 yard zero. As you cranked in more elevation you would be off the top of the paper even before getting in half of what you needed to finish your test.
It's confusing at first when you read how to do this test but when you see it done it's really pretty simple and gives you a lot of information just in that one test.
Topstrap
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Russell3812</div><div class="ubbcode-body">It's been awhile since my original post. I had the chance yesterday to go out to my local range and do a vertical line test. I placed my target at 100 yards. After establishing my 100 yard zero I fired shots from the bottom of the target up dialing elevation in 100 yard increments up to 700. For the most part the shots tracked straight up the line. I say for the most part because it was more difficult than I thought to dial in all this elevation and fit the shots on my 12" target. But the results I got from this test proved to me that the scope is tracking as it should straight up and down. </div></div>
I'm still not sure you did that verticle tracking test correctly after reading your response. You can't put that much elevation onto a 12" target and still be seeing your hits if you are still aiming at the same mark on your target you started with at your 100 yard zero. As you cranked in more elevation you would be off the top of the paper even before getting in half of what you needed to finish your test.
It's confusing at first when you read how to do this test but when you see it done it's really pretty simple and gives you a lot of information just in that one test.
Topstrap
Re: Technique
You want to box test at least 36 inches vertical. What you can't see at 12 inches will show up at 36 inches. If I have the travel left in the scope, I'll go another 18 inches. The more distance you have, the easier to calculate the exact travel per click on your scope.
Do the same test with as much travel in the horizontal direction as you can.
You want to box test at least 36 inches vertical. What you can't see at 12 inches will show up at 36 inches. If I have the travel left in the scope, I'll go another 18 inches. The more distance you have, the easier to calculate the exact travel per click on your scope.
Do the same test with as much travel in the horizontal direction as you can.
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