Scope failed tall target test....🤬

Greyfox

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I will always check a new scope by projecting the reticle on the wall with a plumb line. Do this using a flashlight directed through the scope from the objective end, three feet from the wall. With the scope secured, you can check the reticle relationship to the turret using a level. You can also check the reticle’s s alignment with the plumb line by dialing elevation. The projected reticle should track with the plumb line.
I use this approach to:
Alignment the reticle to the centerline of the barrel, check action rail alignment, and plumb the scope, I have rarely if ever had to re-adjust my mounts for plumb when verifying by shooting a tall-test target. Scope bases are always bedded to the receiver, and depending on the type of rings, lapped for contact area with the scope tube.
 

IDHntr77

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I used a Scope Setter
to mount my scope in the rings. I was amazed at how much even just tightening the ring screws caused my optic to twist. Took me several tries until I was happy with the result. I don't have a really nice vise so I'm not sure how else I would have done it.
 

L.Sherm

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I've never seen one or looked for one there might be one on youtube.
You can also bed your rings to center the windage or build elevation into your rings if you have alot of windage cranked into your scope to get on target or want m.o.a for long range.
The windage is what got me to start bedding a set of rings after I did the first one I asked myself why I didnt start doing this long ago.
No amount of lapping can cure poor windage or elevation alignment.
 

kyshooter74

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I would like to read about or see a video of this process if you could suggest one please? Thanks
It’s very easy to do and straight forward. 1 piece bases being the easiest. Talley type or weaver 2 piece next in ease of the job. The combination 1 base and ring combo took some thinking lol. It doesn’t matter the quality of the base you buy. Mainly because I’ve found it’s the action that’s off in being level front to back.
 

djfergus

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Are you sure your scope is mounted stress free, by that I mean more often than not when you put a rail on 700 actions and srew one end down the other end has a gap on the other end meaning no way can it not have a banana shape when tightened down.
I know your using Talleys which if I remember correctly are 2 piece which means the same principal when you torque the scope down. I'm not saying it's your problem but it's something to look at and eliminate it's why anymore I dont care if there NF or spuhr mounts it can very well be the actions mounting points I bed the rings and rail if needed which is atleast 75% of the time
I've had rails on several 700 uneven / banana shaped. I've bedded the rails just as you mentioned. I use tin foil to cover the action, poke holes in foil for the screws and shoe polish on the foil
 

KY_Windage

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Something that I have found with a couple of rifle scopes is that the cross hairs can be canted when the physical body of the scope is leveled to the gun but still track up and down with no issue.
That will not happen if the rifle is accurate. It is an immutable rule of physics that if your reticle does not point at the center of your bore, the track line will diverge left or right from the plumb line as you crank up more and more.

Doc, one other thing - use a plumb-bob to plumb your target, not a level. You can make one in two minutes by simply tying a weight on a piece of heavy twine. It is too easy to be off a bit when reading a bubble level.

I don't want to insult you or your rifle but part of the problem is also that your groups are so large and you are firing only three (or two) shots. I get the groups down at 100 yards before I even worry about tracking, because if the rifle will not group well it is going to be useless at long range anyway.
 

ChrisH56

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I have seen shooters create targets that are set up with specific MOA or Mils spacing to test their scopes without shooting (similar to a tall target test target). Plumb the target at 100 yards and then mount your rifle in some way (lead sled, etc) to hold it in a level (plumb) position. Align your reticle with the center line of the target and at the top of the target. Then turn your elevation knob and see if the center of your cross hairs stay on the plum line of the target as it moves up and down. If off, you can then rotate your scope to align with the plumb line of the target. At the same time you can move your elevation a specific amount of MOA or MILS to correspond to the marks you set your target up with to see if your scope tracks correctly. I hope I have explained this correctly......sometimes it is hard to explain what you are thinking.
 

skipglo

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So I have a Leupold VX6 on my CA 6.5 PRC. Rifle shoots really well, I’ve got a load worked up that is consistent and I’m feeling good about this fall until the tall target test. When I dial up, I get a 1.5-2” shift to the right. I ran the test 4 times. Made sure the target was plumb with a level, used levels to mount the scope, and even tried rotating the scope counter clockwise (since the shift was to the right). Nothing has worked. No matter what I try, when I dial up, I get a POI shift to the right. I know there are a lot of things that can cause this. I’m using Talley one piece rings for the mount. I’ve remounted the scope twice. I’ve got a NF I’m going to put on it to see if it is the scope or the mounts, or the receiver. Anyone have any other suggestions? Would a bore sighting tool show the discrepancy?? I got the scope from Holland’s with his reticle in it. I’m going to call them on Monday to see what they have to say. Is it possible I just have a bad scope?? Thanks.
Glenn
What happens when you dial back down? Try going down past zero and see if it goes down and left...if it does I've had this problem ....so I will keep it short.....put a level on the base! Find a level surface and run your scope level (small level) down the base in small steps. If the base is canted to the left...as you elevate the scope will travel high and right! This problem cost me Three new scopes and a new rifle, and a re-barrel.
 

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Bwana Clay

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So I have a Leupold VX6 on my CA 6.5 PRC. Rifle shoots really well, I’ve got a load worked up that is consistent and I’m feeling good about this fall until the tall target test. When I dial up, I get a 1.5-2” shift to the right. I ran the test 4 times. Made sure the target was plumb with a level, used levels to mount the scope, and even tried rotating the scope counter clockwise (since the shift was to the right). Nothing has worked. No matter what I try, when I dial up, I get a POI shift to the right. I know there are a lot of things that can cause this. I’m using Talley one piece rings for the mount. I’ve remounted the scope twice. I’ve got a NF I’m going to put on it to see if it is the scope or the mounts, or the receiver. Anyone have any other suggestions? Would a bore sighting tool show the discrepancy?? I got the scope from Holland’s with his reticle in it. I’m going to call them on Monday to see what they have to say. Is it possible I just have a bad scope?? Thanks.
Glenn
 

Bwana Clay

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Sep 11, 2019
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Kerrville, Texas
So I have a Leupold VX6 on my CA 6.5 PRC. Rifle shoots really well, I’ve got a load worked up that is consistent and I’m feeling good about this fall until the tall target test. When I dial up, I get a 1.5-2” shift to the right. I ran the test 4 times. Made sure the target was plumb with a level, used levels to mount the scope, and even tried rotating the scope counter clockwise (since the shift was to the right). Nothing has worked. No matter what I try, when I dial up, I get a POI shift to the right. I know there are a lot of things that can cause this. I’m using Talley one piece rings for the mount. I’ve remounted the scope twice. I’ve got a NF I’m going to put on it to see if it is the scope or the mounts, or the receiver. Anyone have any other suggestions? Would a bore sighting tool show the discrepancy?? I got the scope from Holland’s with his reticle in it. I’m going to call them on Monday to see what they have to say. Is it possible I just have a bad scope?? Thanks.
Glenn
Glenn,
I have a VX6 that also failed the ladder test. I sent it back to Leupold, they installed a new erector system and tested. I have shot it a lot since then and it tracks perfectly. Call them first and tell them your problem.
Good Luck,
Bwana Clay
 

SMK1000plus

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Another theory:
The problem is not with increasing elevation but in reducing elevation. How many more down clicks are left on the scope when set for 100 yards?
Bob is correct, if your scope is nearly bottomed-out of elevation adjustment, it could be the inner scope tube has tension on it from touching the external scope tube (body) that relaxes as you adjust the elevation up enough to clear the side pressure. That would explain the sudden shift in windage POI that then POI remains constant the rest of the travel up.

Great point Bob!

I usually pick my scope base off the formula:
Scope base cant equals 1/2 the actual total elevation adjustment of the scope, minus 10 MOA.

ie: a scope with 80 MOA or 24 MILs elevation adjustment would use 80 MOA ÷ 2 = 40 MOA, then subtract 10 MOA = a needed scope base with a maximum of 30 MOA. That leaves plent of windage adjustment when the scope is set to zero at 100.
 

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