Turret Not Level

[Brendan]

I'll add a little more color on how I use it. Here's a link with a little more detail:

EXD Engineering Vertical Reticle Instrument — Firearms Insider

I'm about to share with you one of the most useful tools in my gun drawer. I'm almost certain that unless you already have some sort of trick or technique for mounting an optic squarely level to a firearm, you'll want to pick up one of these for yourself after reading this review. The EXD Engin

www.firearmsinsider.tv

The tool squares up to your scope and the barrel using V-blocks, and then has a bubble level that lets you level the gun without needing a flat surface like a turret cap (Barrel, scope, and bubble level are aligned). Then with the gun leveled, you compare the reticle to a plumb bob, and adjust the scope until the vertical line of the reticle is parallel to the plumb bob. Tighten down your rings checking that reticle doesn't move as you snug things down. Double check by leveling up the gun again, and checking against the plumb bob. Done, and done.....

 

[General RE LEE]

Let me drop this question. Can one eyeball the reticle level and get acceptable accuracy out to 500-600 yards?


Sent from my iPhone using Tapatalk

 

[rayporter]

remove the bolt and look down the bore after you plumb the scope. if the rope bisects the bore you are as perfect as it gets.

 

[Brendan]

Let me drop this question. Can one eyeball the reticle level and get acceptable accuracy out to 500-600 yards?

In my opinion, no, but your definition of acceptable might be different than mine....

You could always eyeball it, then test at different ranges after sighting in at 100 and see if POI moves off center. If you're hitting with "acceptable" accuracy - you're fine. Depends on how good you are at eyeballing it.

 

[Cahunter805]

Lots of good info already posted.

Ill drop a question also. How many of you run a tall target test to verify the reticle and your tracking is on?

 

[Lawnboi]

The tool Brendan lists is the best that I have used. Very simple and dead on every time. You align the elevation turret center line of travel to the bore. This is done by leveling the turret post, or the bottom of the turret housing. The reticle alignment isn't actually relevant, but any quality optic will have an aligned reticle. Think about it, the barrel follows the mechanical movement of the turret. The reticle alignment is only important for hold off to off center aiming points on the reticle.

I see several notes on the plumb bob and reticle alignment to that. That isn't correct if you want the barrel to track with the turret. It works, but only if the reticle is aligned to the turret. Not the other way around.

Jeremy

Interesting. So your trying to match the reticle to the bore? The bore is round. I try to find where my action/stock is about level, but it’s not easy or very accurate in my opinion.

if your reticle is not straight on a plumb line, when your scope level is where you where you want it, regardless of its orientation to the bore, you are introducing error left or right.
The plumb bob method I got straight out of a nightforce scope owners manual, I don’t doubt them, and it’s hard to argue it when you wrap your head around it.

I wish I could link the write up but I had just read an article about how little your bore being level actually makes on the shot, and that it’s more about your scope tracking correctly.

And if your not dialing just eyeball’er and send them.
And even dialing at nominal distances I’d bet a level won’t make or break it.

This is not even taking into account any retinal misalignment inside the scope, assuming the dials track perfectly up and down.

 

[CBECK61]

Lots of good info already posted.

Ill drop a question also. How many of you run a tall target test to verify the reticle and your tracking is on?

Guilty. I like to get the standard targets that have 5 diamonds. Shoot the center adjust up 6in left 6 inches then over 12 down 12 and over 12. This shows me a couple things. You can see that your scope isn't tracking on plain but more importantly if it is tracking accurately and consistently.

 

[Lawnboi]

Lots of good info already posted.

Ill drop a question also. How many of you run a tall target test to verify the reticle and your tracking is on?

I need to on some of my guns; I suspect my third athlon that I got warrantied has a canted reticle. Even better yet who test tracking on their scopes prior to mounting?

 

[Wapiti1]

Interesting. So your trying to match the reticle to the bore? The bore is round. I try to find where my action/stock is about level, but it’s not easy or very accurate in my opinion.

if your reticle is not straight on a plumb line, when your scope level is where you where you want it, regardless of its orientation to the bore, you are introducing error left or right.
The plumb bob method I got straight out of a nightforce scope owners manual, I don’t doubt them, and it’s hard to argue it when you wrap your head around it.

I wish I could link the write up but I had just read an article about how little your bore being level actually makes on the shot, and that it’s more about your scope tracking correctly.

And if your not dialing just eyeball’er and send them.
And even dialing at nominal distances I’d bet a level won’t make or break it.

This is not even taking into account any retinal misalignment inside the scope, assuming the dials track perfectly up and down.

Not quite what I am trying to say. You are trying to align the travel of the barrel in a straight line to the movement of the reticle when you turn the elevation turret. The barrel must move in a line dead on the movement of the reticle as you turn the turret.

If the reticle is canted left 3 degrees relative to the turret movement, and you level the bore to the reticle, the turret will move the center of the reticle at a 3 degree angle. If you align the turret to the bore, the center of the reticle maintains the same linear relationship to the bore and the barrel will track with the turret. Even though the reticle will look canted.

Nightforce has excellent attention to detail and QC, so the reticle and turrets are always in alignment.

Here is what is happening. The center of the reticle is the aiming point, and it stays in the same spot if you drew a line between you and the target through the scope reticle. As you turn the turret, the barrel angle moves up or down, but the line of sight remains the same from you through the reticle to the target. So the barrel must track with the turret, not the reticle. The turrets dictate where things go, the reticle is literally along for the ride.

I could draw it out much better than I can put it to words.

This helps explain it:http://www.highpoweroptics.com/reticle-alignment-i-96.html

Jeremy

 

[Brendan]

Interesting. So your trying to match the reticle to the bore?

What I'm doing is drawing a line from center of barrel through center of scope (based on OD of the barrel and OD of the Scope Bell) and making sure that is vertical, and parallel to the vertical line of the reticle using the tool I mentioned. So - level the rifle based on bore / scope alignment, and then match reticle to a plumb bob to make sure reticle is vertical.

That's not perfect if you have a bore not true to OD of the barrel, or if scope bell is not true to the reticle. But, closer than anything else I've found, and test / verify after. (Side note, I do have the defensive edge kit I mentioned in post #2, and check for other level surfaces on the rifle, scope, rail that I can verify against)

I don't shoot "Long Range" (yet) but I'm sure most verify with some sort of a tall target / tracking test against a plumb bob or vertical line of sorts. I do limited testing at the range and haven't had it fail me yet.

 

[Lawnboi]

Not quite what I am trying to say. You are trying to align the travel of the barrel in a straight line to the movement of the reticle when you turn the elevation turret. The barrel must move in a line dead on the movement of the reticle as you turn the turret.

If the reticle is canted left 3 degrees relative to the turret movement, and you level the bore to the reticle, the turret will move the center of the reticle at a 3 degree angle. If you align the turret to the bore, the center of the reticle maintains the same linear relationship to the bore and the barrel will track with the turret. Even though the reticle will look canted.

Nightforce has excellent attention to detail and QC, so the reticle and turrets are always in alignment.

Here is what is happening. The center of the reticle is the aiming point, and it stays in the same spot if you drew a line between you and the target through the scope reticle. As you turn the turret, the barrel angle moves up or down, but the line of sight remains the same from you through the reticle to the target. So the barrel must track with the turret, not the reticle. The turrets dictate where things go, the reticle is literally along for the ride.

I could draw it out much better than I can put it to words.

This helps explain it:http://www.highpoweroptics.com/reticle-alignment-i-96.html

Jeremy

I read your link and think we are talking two separate things. I’m speaking of the reticle in the scope being perfectly plumb. Your bullet leaves the barrel and gravity takes over, gravity only goes one way.

I’m not seeing how the above picture in your link even pertains to modern optics? I have no way other than shimming my scope left or right to move my scope. In fact most bases discussed here have no way to adjust your scope left or right to align with the barrel. I guess I have always just assumed it was machined in line or damn close to.

Of course if your bases are so garbled up that your scope is not aligned with your barrel things will get messed up. I’m talking reticle and a cant introducing variables when dialing.

In fact the link you posted has noting to do with reticle alignment, it has do some with aligning a scope on a plane with the barrel, which with most rings and bases, is not something commonly adjustable.

For hohos and hahas let’s hypothetically say your scope is on the same plane as your barrel and your reticle is canted a few degrees. Now you dial 10 Mils of elevation, because your reticle is not tracking straight up and down (it’s canted). Your impact shifts more and more as you dial, as it comes off plumb. Your bullet is going to follow gravity, along with other predictable variables.

 

[Lawnboi]

What I'm doing is drawing a line from center of barrel through center of scope (based on OD of the barrel and OD of the Scope Bell) and making sure that is vertical, and parallel to the vertical line of the reticle using the tool I mentioned. So - level the rifle based on bore / scope alignment, and then match reticle to a plumb bob to make sure reticle is vertical.

That's not perfect if you have a bore not true to OD of the barrel, or if scope bell is not true to the reticle. But, closer than anything else I've found, and test / verify after. (Side note, I do have the defensive edge kit I mentioned in post #2, and check for other level surfaces on the rifle, scope, rail that I can verify against)

I don't shoot "Long Range" (yet) but I'm sure most verify with some sort of a tall target / tracking test against a plumb bob or vertical line of sorts. I do limited testing at the range and haven't had it fail me yet.

I also would not call myself anywhere near an expert in the subject. That said it’s pretty easy to wrap my head around my reticle not tracking straight up and down(on a plumb line) messing with dials or even holds if it was that canted.

I did a bunch of reading when I got my first nightforce years ago and read that in the manual, because up until then I just used levels and what not when what I really needed was 15 feet of paracord and a bag of sand

 

[Lawnboi]

The Truth about Rifle cant and leveling your reticle.

The purpose of this post is hopefully to shed light on some myths about rifle cant and help potential long range hunters set up their rifles with confidence. A while back a friend asked me take a look at his rifle as he was having difficulty making accurate long range shots from an otherwise...

www.rokslide.com

This thread is also a good read on the subject.

 

[Wapiti1]

I also would not call myself anywhere near an expert in the subject. That said it’s pretty easy to wrap my head around my reticle not tracking straight up and down(on a plumb line) messing with dials or even holds if it was that canted.

I did a bunch of reading when I got my first nightforce years ago and read that in the manual, because up until then I just used levels and what not when what I really needed was 15 feet of paracord and a bag of sand

I think we are talking about the same thing. Ignore the left right scope alignment photo. The picture on the left in the article is the important one. Imagine the reticle is canted, but the turret is in line with the bore. That is what I am considering. If you align the reticle plumb, then the turret is off, and dialing is also off. This isn't common, but it can happen. I've seen it in two scopes, one European and one domestic.

this might explain what I am talking about better:http://bulletin.accurateshooter.com...ers-stop-selling-scopes-with-canted-reticles/

Jeremy

 

[Lawnboi]

I think we are talking about the same thing. Ignore the left right scope alignment photo. The picture on the left in the article is the important one. Imagine the reticle is canted, but the turret is in line with the bore. That is what I am considering. If you align the reticle plumb, then the turret is off, and dialing is also off. This isn't common, but it can happen. I've seen it in two scopes, one European and one domestic.

this might explain what I am talking about better:http://bulletin.accurateshooter.com...ers-stop-selling-scopes-with-canted-reticles/

Jeremy

I still am not on the same page. The link in your last post is on the same line of what I’m talking. If the reticle is not perfectly vertical to the turrets, or gravity, your going to have problems....
Do appreciate the conversation though

 

[Brendan]

I still am not on the same page. The link in your last post is on the same line of what I’m talking. If the reticle is not perfectly vertical to the turrets, or gravity, your going to have problems....
Do appreciate the conversation though

I get what you're saying.

if Reticle not perfectly vertical to the turrets, then when dialing, the reticle moves along the axis of the turret, not along the axis of the reticle, right? So, in this case you can't level a reticle to a plumb bob and expect results to be correct when dialing. But, in this scenario, what matters is the axis of the turret itself, and not necessarily the cap. Machining there could throw things off slightly.

So, I personally haven't run into this one, becuase the one scope I had a small amount of misalignment was a BDC scope, so once sighted in what mattered was the reticle, not the turret... And, I can't remember if I checked cap or the turret itself....

 

[Wapiti1]

I still am not on the same page. The link in your last post is on the same line of what I’m talking. If the reticle is not perfectly vertical to the turrets, or gravity, your going to have problems....
Do appreciate the conversation though

We are saying the same thing. The only difference is that I am suggesting you align to the turret travel instead of the reticle. Think of a target dot scope with no horizontal or vertical crosshair. How do you align that? You align the turret to the vertical travel (arc of gravity) of the bullet, which typically works out to be the center of the bore. Then the bullet follows the turret.

Brendan states it correctly. Not sure why I couldn't say it that simply. Reticle to turret misalignment is the problem I am concerned with. If it exists in your scope, aligning to the reticle introduces error because now the turret is off axis. Aligning to the turret removes that error for the center aiming point of the reticle. The center of the reticle always moves with the turret. You're hosed if you use any other part of the reticle for holds though. The reticle will look canted, but tracking of the center aiming point will be spot on.

I could sketch it out, but I don't think I am describing it properly.

Jeremy

 

[Lawnboi]

We are saying the same thing. The only difference is that I am suggesting you align to the turret travel instead of the reticle. Think of a target dot scope with no horizontal or vertical crosshair. How do you align that? You align the turret to the vertical travel (arc of gravity) of the bullet, which typically works out to be the center of the bore. Then the bullet follows the turret.

Brendan states it correctly. Not sure why I couldn't say it that simply. Reticle to turret misalignment is the problem I am concerned with. If it exists in your scope, aligning to the reticle introduces error because now the turret is off axis. Aligning to the turret removes that error for the center aiming point of the reticle. The center of the reticle always moves with the turret. You're hosed if you use any other part of the reticle for holds though. The reticle will look canted, but tracking of the center aiming point will be spot on.

I could sketch it out, but I don't think I am describing it properly.

Jeremy

If the turret is not aligned with the reticle that is a scope that needs to go back. Wether the turret is canted, or the reticle is canted, it’s going to eventually do the same thing when you dial, which is take it off that vertical line. If both are off It would only be worse.

In the same respect, I’d your mount holes or barrel, or mounts are not aligned with the action, the gun is going to take more to get fixed than some scope magic

Edit, I do see what I think your trying to say, the scope must be directly over the bore so it all tracks straight. I can wrap my head around that, but the scope and the turrets still need to track completely vertically as well. Cant or turret misalignment with the reticle will cause impact shift the further you dial away from zero.

This thread is making me want to do some tall target tests.

 

[Cahunter805]

Where is Form when you need him!!

A tall target test is a great tool not only to help determine if the reticle is canted but also if your scope dials correctly and return to zero also.

 

[Wapiti1]

I was simply trying to say that you can't just level the reticle to the bore and assume all is well.

Edit, I do see what I think your trying to say, the scope must be directly over the bore so it all tracks straight. I can wrap my head around that, but the scope and the turrets still need to track completely vertically as well. Cant or turret misalignment with the reticle will cause impact shift the further you dial away from zero.

This thread is making me want to do some tall target tests.

That is what I was trying very poorly to say. Just aligning to the reticle isn't enough. You have to check the turret alignment as well, and for me, I do that first, then check the reticle. IF the mechanics aren't aligned, nothing is going to work right regardless of what the reticle looks like.

Keep in mind, you can pass a tall target test with a canted reticle as long as the mechanics are lined up and the rifle is level. The reticle will be cocked and drive you nuts, but it will track just fine up and down the target. Then you send the scope in to be fixed.

Jeremy