CANT , and it's effect ?

[Scotchmo]

.... A CONVERGENCE ANGLE of BORE to LOS is CREATED by the height of mounting. ...

... ANY HIGHER MOUNTING of the scope produces a STEEPER angle between bore and LOS. SIMPLE GEOMETRY. ..

...those 2 distinct angles (STEEPER for ANY HIGHER SIGHT) then DIVERGE from LOS ...

The over-simplification of following the bore-line is not correct in this instance. Once the projectile leaves the muzzle, it no longer follows the bore-line, it follows the trajectory. The higher scope will have LESS divergence angle at the far targets.

 

[bandg]

"I think I follow what you’re saying" Apparently not. WHY WHY WHY do you feel the "NEED" to even mention MIL-DOTS at all? Gorilla dust and circular logic again.

READ what scotchmo SPECIFICALLY wrote. He wrote EXACTLY THAT he was referring to the EXACT case of "holding over with the crosshair" (no mention of mil-dots) but then stated the erroneous conclusion. I'm very glad that happened because now YOU are on record as agreeing with him. YOU ARE BOTH WRONG. NEITHER OF YOU UNDERSTAND THE BASIC GEOMETRY. The constant need to mention mil-dots illustrates that you don't understand. NO RELATION TO MIL-DOTS HERE. 

"That’s why the high scope would produce less error when using the “just aim high” approach"

WRONG. INCORRECT. IN ERROR. Can't think of any other way to say this without being derogatory. YOU DON'T UNDERSTAND.

EVERY SINGLE SHOOTER CAN TEST THIS FOR THEMSELVES. WHAT YOU STATE IS IMPOSSIBLE. EVEN SZOTTESFELD UNDERSTOOD THAT (ONCE THOSE MEAN OLD LONG RANGE "FIREARM" SHOOTERS POINTED IT OUT TO HIM) AND ADMITTED SO.

In effect, you are stating here that he (Szottesfeld) had all the "important" stuff (the stuff you agree with) right but made an error when he ackowledged the "exception" (the stuff you don't agree with). Egocentrism exemplified.

Again, any individual who wants to test this specific issue can do so with some effort-

1)take your currently owned zeroed scoped rifle and shoot at 3x your near zero distance after shooting to determine the correct amount of crosshair holdover ("incorrect" or "improvised" as these guys would call it but note that you can reliably hit the target "aiming that way")

2)using that "aim point" that YOU verify by shooting trial and error, then cant the gun any given specific amount, shoot, and measure horizontal miss distance. Relatively easily done but the canted shooting can be pretty difficult.

3)now the more difficult part that will take more effort-get SOME MOUNT that will raise the scope height (doubled is good since it clearly and easily illustrates the changes produced from what you already have but it doesn't have to be doubled necessarily) and repeat the exact above process with the higher scope (shoot to determine the necessary holdover amount for THAT HIGHER scope then shoot with cant). OBSERVE THAT THE HIGHER SCOPE PRODUCES MORE HORIZONTAL MISS DISTANCE THAN DOES THE LOWER SCOPE.

ANYONE can do this and see for themselves who is correct here. It takes some effort and unfortunately most people will not take the time to do so (I certainly can't blame them) and they would then have to CHOOSE which view they accept. That's fine too. People could even choose to ignore all of this and just go shoot. Also fine. Such won't impact my shooting at all. But IF ANYONE really wants to UNDERSTAND, try it. I have NEVER mounted 2 scopes physically at the same time on a single rifle. WHY? Because the process as was described does not represent the situation accurately AND NO ONE SHOOTS THAT WAY IN THE REAL WORLD. I have done PRECISELY EXACTLY what I've described with 2 SEPARATE scopes of different heights mounted on the same rifle firing the same projectile for an EXACT REAL WORLD ACTUALLY VALID SHOOTING COMPARISON between the effect of high and low scope mounting. WHY did I do so with 2 individual separate (but different height) scopes? Because that PRODUCES A REAL WORLD ACTUAL SHOOTING DIRECT COMPARISON of high to low scope which can be tested for any distance and that ANYONE could do and could see the results for themselves. NO FORMULAS, NO DIAGRAMS, NO THEORY. Just good ole physical measurable results.

Note that I suggested 3X near zero distance and doubled scope height. Such specifics aren't necessary because what I've described is based on simple geometry. But for a CLEAR EASY TO SEE RESULT, doubling height illustrates the effect more than 1.25X or 1.5X the height and 3X distance illustrates the effect better than 2 times distance. ALSO, one must be aware of any wind drift that may introduce "noise" into the results and therefore doing such a trial is best done on a still day, but if the wind is CONSISTENT (usually rarely happens) then the effect can still be clearly seen. But calm conditions are better. But any two scope heights could be used and any distance beyond near zero could be used. IT DOESN"T MATTER BECAUSE THE EFFECT IS A SIMPLE GEOMETRIC EFFECT THAT IS CONSTANT WITH RELATION TO HEIGHT AND DISTANCE.

 

[nervoustrig]

1)take your currently owned zeroed scoped rifle and shoot at 3x your near zero distance after shooting to determine the correct amount of crosshair holdover ("incorrect" or "improvised" as these guys would call it but note that you can reliably hit the target "aiming that way")

2)using that "aim point" that YOU verify by shooting trial and error, then cant the gun any given specific amount, shoot, and measure horizontal miss distance. Relatively easily done but the canted shooting can be pretty difficult.

3)now the more difficult part that will take more effort-get SOME MOUNT that will raise the scope height (doubled is good since it clearly and easily illustrates the changes produced from what you already have but it doesn't have to be doubled necessarily) and repeat the exact above process with the higher scope (shoot to determine the necessary holdover amount for THAT HIGHER scope then shoot with cant). OBSERVE THAT THE HIGHER SCOPE PRODUCES MORE HORIZONTAL MISS DISTANCE THAN DOES THE LOWER SCOPE.

I’m so happy to see you spell it out. You just described the two scope arrangement, only doing it in two steps instead of one.

The holdover points you experimentally come up with for each scope, they correspond to an overlapping point of aim at the target...the identical point of aim that I have been talking about. Identical points of aim cannot cause different errors.

 

[bandg]

.... A CONVERGENCE ANGLE of BORE to LOS is CREATED by the height of mounting. ...

... ANY HIGHER MOUNTING of the scope produces a STEEPER angle between bore and LOS. SIMPLE GEOMETRY. ..

...those 2 distinct angles (STEEPER for ANY HIGHER SIGHT) then DIVERGE from LOS ...

The over-simplification of following the bore-line is not correct in this instance. Once the projectile leaves the muzzle, it no longer follows the bore-line, it follows the trajectory. The higher scope will have LESS divergence angle at the far targets.

"The over-simplification of following the bore-line is not correct in this instance. Once the projectile leaves the muzzle, it no longer follows the bore-line, it follows the trajectory. The higher scope will have LESS divergence angle at the far targets."

A couple of things here for those that are thinking. The beautiful illustration by scotchmo shows 2 DISTINCT NEAR ZERO DISTANCES. Sometimes "it must be the same distance" and sometimes it doesn't seem to matter. No consistency, circular.

What you post above is CORRECT in the sense that drop will occur but INCORRECT in conclusion. GRAVITY WHICH IS A CONSTANT CAUSES THE DROP. GRAVITY (ALONG WITH SPECIFIC GUN/PROJECTILE FACTORS SUCH AS WEIGHT/VELOCITY/BC) "TOGETHER" PRODUCE TRAJECTORY. AND IT ISN"T THE ANGLE YOU ILLUSTRATE THAT CAUSES THE HORIZONTAL DISPLACEMENT. IT IS THE OTHER ANGLE I.E. BORE TO LOS THAT IS RELEVANT TO THAT HORIZONTAL DISPLACEMENT. ANGLE ALONE causes the horizontal displacement, you are illustrating the WRONG ANGLE for relevance. The angle that you marked is IRRELEVANT here. YES, it occurs. But it is tied to drop. The RELEVANT angle which you DIDN'T mark is to the left, between bore and LOS. THAT ANGLE determines horizontal displacement. Unless one can grasp this, one does not understand.

I believe that you often state that "there is no cant error without drop". This only illustrates correlation, not causation. DROP DOES NOT CAUSE CANT ERROR. Drop happens simultaneously with any horizontal displacement caused by canting, but one doesn't cause the other. A CORRELATION, NOT A CAUSATION.

Unless one can grasp this, one does not understand. The testing I described above will illustrate this plainly to ANYONE who wants to UNDERSTAND. All one has to do is perform the necessary scope changes/mounts and shoot. Again, no diagrams (which are interpreted in error here by the user) or formulas or theories. Just observable actual results from shooting.

Anyone who wants to do the actual testing I described, enjoy the shooting and don't let that "light bulb" blind you when it pops on and realization hits. 

 

[bandg]

1)take your currently owned zeroed scoped rifle and shoot at 3x your near zero distance after shooting to determine the correct amount of crosshair holdover ("incorrect" or "improvised" as these guys would call it but note that you can reliably hit the target "aiming that way")

2)using that "aim point" that YOU verify by shooting trial and error, then cant the gun any given specific amount, shoot, and measure horizontal miss distance. Relatively easily done but the canted shooting can be pretty difficult.

3)now the more difficult part that will take more effort-get SOME MOUNT that will raise the scope height (doubled is good since it clearly and easily illustrates the changes produced from what you already have but it doesn't have to be doubled necessarily) and repeat the exact above process with the higher scope (shoot to determine the necessary holdover amount for THAT HIGHER scope then shoot with cant). OBSERVE THAT THE HIGHER SCOPE PRODUCES MORE HORIZONTAL MISS DISTANCE THAN DOES THE LOWER SCOPE.

I’m so happy to see you spell it out. You just described the two scope arrangement, only doing it in two steps instead of one.

The holdover points you experimentally come up with for each scope, they correspond to an overlapping point of aim at the target...the identical point of aim that I have been talking about. Identical points of aim cannot cause different errors.

Circular, as always. Back to "point of aim" but still viewing it in terms of mil-dots, which you used in your example. Try to follow the conversation. SCOTCHMO mentioned "aiming with the crosshairs" which I subsequently discussed. You STATE, in effect, that you are doing "the same thing". If it is "the same thing" as you insinuate then why not just simply do it the way I described. MUCH MUCH easier to do than what you described. But you cannot, without using DIFFERENT MIL-DOT HOLDOVERS (the same as click-to in your words thus not "identical points of aim") because you would be proven wrong. That's all it takes, just do it as scotchmo mentioned and as I addressed. I know what you would find if you did so. I've done it. I've never diagrammed it and I've never tried to calculate it. I've DONE IT so such other things are irrelevant. Apparently you need to do it in order to understand.

 

[nervoustrig]

I know what you would find if you did so. I've done it. Apparently you need to do it in order to understand.

It’s funny you should say that. Maybe you should follow your own advice. I’ve done the experiment twice.

But you cannot, without using DIFFERENT MIL-DOT HOLDOVERS

Why on earth would I use the same mildot for the two scopes? You want me to deliberately introduce an aiming error? Finally, that explains why you are arguing so.

 

[bandg]

A quick take for tonight. 20th wedding anniversary was today so it was a bit of a late start.

The basic info:

1. QB79 HPA with short LW barrel running RWS Super Field pellets at 780fps (modest velocity and relatively poor BC pellet to ensure sufficient drop)
2. Mounted 2 scopes. Low one at 1.65" above bore, high one at 3.87" above bore.
3. Zeroed both scopes at 30 yards.
4. Shot groups at 50 yards through each scope to determine holdover (1.5 mildot for low scope, 0.8 mildot for high scope)
5. Canted gun 45° and shot a group via the low scope.
6. Canted gun 45° and shot a group via the high scope.

The 2-scope setup:


The groups at 50 yards with the rifle canted 45 degrees:




The vertical error for each group is virtually identical at 2.7". The horizontal errors are 7.2" and 7.5" for the low and high scopes, respectively, which represents a 4% difference. For a crude test cobbled together in an hour, I think it sufficiently demonstrates the concept.

No, you haven't. Anyone wanting to see "circular logic" in action, look at #4 in his description of process for his "2 simultaneous scopes" stuff. I've been illustrating using the crosshairs as the point of aim since scotchmo mentioned it a few posts above and made his erroneous statement there, which I've addressed. I'd swear I see, in this quoted post above in line #4, mil-dots. Is it my imagination? I don't think so. But let me look again. Yep, written right there in #4-mil dots. Why mention mil-dots. Which is stated by the OP here to be the same as click-to. Circular, with gorilla dust, and thus irrelevant.

I'd have to count to see how many times this has been said but again-ANYONE who wants to understand the correct view here can do exactly as has been described. Using the crosshairs to aim, and determining the correct "aim point" (the "incorrect" or "improvised" holdover which surprisingly allows one to reliably hit the target once identified) and not "circling back" to the term mil-dots, and actually shooting a single gun with the two distinct scope height setups in that way, the CORRECT view can be identified.

 

[bandg]

I know what you would find if you did so. I've done it. Apparently you need to do it in order to understand.

It’s funny you should say that. Maybe you should follow your own advice. I’ve done the experiment twice.

But you cannot, without using DIFFERENT MIL-DOT HOLDOVERS

Why on earth would I use the same mildot for the two scopes? You want me to deliberately introduce an aiming error? Finally, that explains why you are arguing so.

"Why on earth would I use the same mildot for the two scopes?" 

More "circular gorilla dust". The discussion since scotchmo made his post doesn't involve mil-dots at all, but does involve the crosshairs. I'm not using mil-dots at all. YOU are the one constantly referring back (circular) to them.

 

[nervoustrig]

Go back and read what you wrote above. You described finding the appropriate holdover for each scope, which of course is the sensible thing. The holdover (e.g. mildot) will be different for each. Then you turn right around and say I “cannot without using different mildot holdovers”.

You’re right about one thing, I can’t when you’re changing the rules as you go.

 

[nervoustrig]

The discussion since scotchmo made his post doesn't involve mil-dots at all, but does involve the crosshairs. I'm not using mil-dots at all. YOU are the one constantly referring back (circular) to them.

“Mildot”’ is for compactness of speech. Feel free to substitute “an experimentally obtained holdover using a plain crosshair reticle”. Same thing, one is just a lot better for readability.

 

[bandg]

ME changing the rules as I go? Now that's rich. AND if "mil-dot" is for compactness of speech, why did you feel the need to use the term? YOU specified MIL-DOT in YOUR post ABOUT the "2 attached scopes". I believe that YOU USED the mil-dots to aim in that "experiment". Am I wrong?

Folks, the ENTIRE thrust of this "discussion" is simple. If one cants while using the crosshairs with a high versus a low scope, a different result occurs than if one cants while using the mil-dots (even if one uses the "correct" mil-dot for the scope/distance) in the same high versus low scopes. 

As I will repeat again, ANYONE who wants to know who is correct here can do the trial for themselves. Then you'll know.

 

[Scotchmo]

I believe that you often state that "there is no cant error without drop". ...

...

If you think that's what I often state, show me some past examples where I stated that.



BTW: I always try to make the distinction when talking about gun cant (trajectory) vs scope cant (LOS). And I know which one is directly related to drop.

 

[nervoustrig]

Folks, the ENTIRE thrust of this "discussion" is simple. If one cants while using the crosshairs with a high versus a low scope, a different result occurs than if one cants while using the mil-dots (even if one uses the "correct" mil-dot for the scope/distance) in the same high versus low scopes.

By including the bold part, you are absolutely wrong.

 

[bandg]

Good grief. I think my statement was crystal clear. So exactly concisely WHAT are you trying to say? Should you use a "different" mil-dot for each case or the "same" mil-dot for each case, in your estimation? It seems that if one is going to "use" mil-dots, he would want to use the "correct" mil-dot.

 

[nervoustrig]

When using the correct mildot for the distance, the point of aim for each scope is identical. Therefore, however much the pellet misses the mark due to canting, it is by the same amount for either scope.

 

[bandg]

Scotchmo

Accuracy: 

Member

I believe that you often state that "there is no cant error without drop". …

…

If you think that's what I often state, show me some past examples where I stated that.



BTW: I always try to make the distinction when talking about gun cant (trajectory) vs scope cant (LOS). And I know which one is directly related to drop.

... So your statement that "it will hit left an amount equal to drop" is simply and plainly incorrect. And as long as you adhered to such a view, you do not understand.

With an uncanted gun, the barrel points slightly upward to compensate for drop. When you cant the gun 90 degrees to the left, the barrel now points slightly left, so that is where the poi will now be.

This picture has the barrel pointing to the right, but same affect. Windage error = drop distance:

I think we are making progress, as scope height is no longer part of the discussion. It's now about drop (gravity) and cant angle. And that is what determines gun cant errors.

"It's now about drop (gravity) and cant angle. And that is what determines gun cant errors."

This is close, for now, as you state angle (correctly) AND GRAVITY(incorrectly) is what "determines gun cant errors". But I believe I can find a direct quote from you stating that there can be no cant error without drop.

Scotchmo

Accuracy: 

Member

I like the deflection on the second part. "Short answer". I will wait for the long answer. I'll write the question again. With 2 different height scopes on the same rifle, zeroed at 20 yards (2 zero method) for each, will the higher mounted scope produce more horizontal cant error at it's far zero than the lower mounted scope will at it's far zero given the same amount of cant in degrees?

OK – a longer answer:

"…Consider a single rifle. A higher velocity accurate air rifle shooting a good BC pellet. …"

Then lets just say that the velocity is so high that gravity has no significant affect. In other words, there will be no cant error from gravity. We can model the trajectory as a straight line. That simplifies the explanation. Now we can look solely at your assertion that the different LOS from different scopes heights causes a difference in cant errors.

So we are having to "assume" that gravity will cause no cant error. Sure sounds like the person making that statement believes that gravity DOES cause cant errors because we are having to use an extreme example and "assume" that it doesn't. Getting closer but I believe I will find the quote. I'm almost certain you stated it verbatim.

Scotchmo

Accuracy: 

Member

…



scotchmo-"Please diagram the exception so I can better understand what you are describing."

You've basically already done about half of that, but as with every person who holds the Szottesfeld view, you stopped a bit short. That is the FATAL ERROR for Szottesfeld. Go back to your B0 and B90 diagram. Redo that illustration using a SIDE ON view but with a SINGLE PAGE SHOWING THE HIGH SCOPE, BORE, AND THAT CONVERGENCE ANGLE TO TARGET and a second SINGLE PAGE SHOWING THE LOW SCOPE, BORE, AND THAT CONVERGENCE ANGLE TO TARGET. REMEMBER to use a COMMON DISTANCE TO TARGET (the basis for the two zero method). Place the scope and muzzle to the left side of both diagrams and the target near the center. …

Now the critical part. EXTEND EACH "BORE LINE" PAST THE "TARGET" and across the page to the right. You will observe that, as you get further and further beyond the "target" (increasing range), both lines continually DIVERGE FROM LOS but the steeper angle of the higher sight causes it to progressively be FURTHER DIVERGED from LOS

…

"…Now the critical part. EXTEND EACH "BORE LINE" PAST THE "TARGET" and across the page to the right. You will observe that, as you get further and further beyond the "target" (increasing range), both lines continually DIVERGE FROM LOS but the steeper angle of the higher sight causes it to progressively be FURTHER DIVERGED from LOS…"

Once you extend "PAST THE "TARGET""(target plane), you are now at a farther disatnce. Any divergence is then a range error. There is no divergence at the target.

"…Redo that illustration using a SIDE ON view but with a SINGLE PAGE SHOWING THE HIGH SCOPE, BORE, AND THAT CONVERGENCE ANGLE TO TARGET and a second SINGLE PAGE SHOWING THE LOW SCOPE, BORE, AND THAT CONVERGENCE ANGLE TO TARGET. REMEMBER to use a COMMON DISTANCE TO TARGET (the basis for the two zero method). Place the scope and muzzle to the left side of both diagrams…"

You should do the diagrams as I've already modeled it in 3D and looked at it from every angle. The only cant error is that resulting from gravity. There is no component introduced by the difference in scope height. If you are able to use 2D descriptive geometry to adequately model it, go ahead. You should then be able to derive the equations that show the actual magnitude of the error. Experiments with precise shooting will confirm the errors predicted by the equations. Photos of dubious shooting accuracy in the wind really tells us nothing definitive. When you have done the proof, including the equations to verify, I might respond again.

It is your assertion that additional cant error is induced by the difference in scope height. You think that is true. My assertion is that is false. Don't ask my to prove a negative. You believe it is true, so it's on you to

scotchmo quote from 6 lines above-

"The only cant error is that resulting from gravity. There is no component introduced by the difference in scope height". Again, sure sounds like someone saying that there is no cant error without drop to me. What else is gravity doing during shooting other than causing drop?

scotchmo quote-"gun cant errors do not happen in zero gravity". Probably a bit facetious but still indicating the view that gravity must be present for cant error to occur, which isn't true. There is a correlation between the two, not a causal relationship between them.

scotchmo quote-"gun cant happens when the gravity vector no longer lies in the horizontal plane. Gravity must be part of the equation". Gravity is always "part of the equation", just not for cant errors. Cant caused by angulation, drop is caused by gravity. The fact that two things are correlated IN NO WAY indicates causation of one to the other.

I could not locate a verbatim quote stating "cant errors can't happen without drop" but I am almost certain you said that. The above quotes surely seem to indicate that you believe it even if I can't find a specific quote where you stated it.

 

[Guest]

At the risk of being controversial, I will not comment on this link.

https://www.shootingillustrated.com/articles/2016/3/28/rifle-scope-reticle-cant/

 

[bandg]

At the risk of being controversial, I will not comment on this link.

https://www.shootingillustrated.com/articles/2016/3/28/rifle-scope-reticle-cant/

Why not? Have the courage of your convictions. Comment away. But seriously, it is a good link. Many will disagree, but it is good IMO. My last post on CANT will follow.

 

[bandg]

A final post to this thread for me. I'm tired of the back and forth, the circular logic, the blending of terms. I'm going to put in a few quotes from various people, most from GTA and stated around 2017 to 2018, and let those quotes speak for themselves. Then I'll offer a final suggestion for the last time to end my participation in this thread.

scotchmo-"With airguns, we often shoot as close as 10 yards. At 10 yards, scope cant issues are 100X as much as it is at 1000 yards." I bet there are a lot of people out there who would disagree with that one.

scotchmo-"any cant is pivoting around the intended POI." WRONG. Any cant is pivoting around the LOS. We aim with the specific sight in question (scope, or open sights, or red dot, or holographic, or laser). Doesn't matter. Canting the gun logically means an erroneous rotating of the gun around the line of aim, or to use another term the LineOfSight (LOS). It does not relate directly to the "intended" PointOfImpact or POI, although the shooter intends to hit that point. WE AIM THE SIGHT AND THE BORE AS WELL AS THE TRAJECTORY BOTH JUST FOLLOW ALONG. CANT is rotating around LOS.

nervoustrigger-"Actually, if the line of sight were in the barrel, cant error would still be a present because of the pellets arced trajectory." I believe EVERYONE can see the fallacy in this. You can spin a round bore 360 degrees with NO "CANT" ERROR AT ALL BECAUSE ONLY GRAVITY IS WORKING IN THAT SITUATION. And he did quickly do a retraction or correction attempt and went on to state something to the effect of he was trying to relate LOS or bore line to trajectory. But such a statement clearly, IMO, indicates an inability to separate LOS from BORE LINE from TRAJECTORY instinctively and how the various forces involved in shooting relate to each.

Finally, this one from a poster whitefox545 who had read the Szottesfeld article-"Scott, read this about a year ago and it seems like it disproves the old story about cant being worse when scope is mounted high. I have shown it to many high quality shooters (some of which were snipers in the service) and they would not con seed (sic) to the theory." Gee whiz, I wonder WHY those dumb and inexperienced "high level shooters" and past "snipers" didn't just take up the Szottesfeld viewpoint. Could it be that their "high level" experience and military "sniper" training had shown them that it was erroneous. Seriously, this was just a quoted post made by an individual on an air gun forum. I certainly don't know who he was or who he had "shown it to" in regards to the Szottesfeld article. But if the post is accurate, my personal decision might have been to go along with the "high level shooters" and prior "snipers" myself. Maybe I'm just funny that way.



Quotes from another well known person in air gun circles-

1)"Scope height makes no difference to cant error at the distance the gun is sighted in."

2)"There is no difference in the cant error between a high and low scope at the range you are zeroed, but there will be a slight difference at all other distances."

3)"A higher scope has less horizontal cant error closer than the zero distance but more horizontal cant error further away."

4)"The vertical cant error does not change with scope height....but the horizontal one certainly does."

Finally, this one from a poster whitefox545 who had read the Szottesfeld article-"Scott, read this about a year ago and it seems like it disproves the old story about cant being worse when scope is mounted high. I have shown it to many high quality shooters (some of which were snipers in the service) and they would not con seed (sic) to the theory." Gee whiz, I wonder WHY those dumb and inexperienced "high level shooters" and past "snipers" didn't just take up the Szottesfeld viewpoint. Could it be that their "high level" experience and military "sniper" training had shown them that such a view was erroneous? Seriously, this was just a quoted post made by an individual on an air gun forum. I certainly don't know who he was or who he had "shown it to" in regards to the Szottesfeld article. But if the post is accurate, my personal decision might have been to go along with the "high level shooters" and prior "snipers" myself. Maybe I'm just funny that way.

The last suggestion I mentioned (and the last time you'll hear it from me)-for those who truly want to know, take your favorite rifle and do the experiment I discussed earlier, Shoot with your standard scope mounting setup currently in place at some multiple of your near zero distance to determine the necessary holdover for that distance and that scope. Then shoot canted a specific amount using that holdover point marked vertically above the intended POI with the crosshair holdover method aimed at that marked point. Observe and mark the horizontal error seen. Then, mount a noticeably higher scope and repeat the EXACT same process to produce a DIRECT low to high scope comparison of cant error produced by each. The more difference in scope height, the better to see the difference. And the larger the multiple of the near zero distance, also the better to see the difference. Wind drift can muddy up the results so do so on a calmer day. Such an effort might be enlightening, to those who want to understand. I know it was to me, many decades ago.

Happy shooting.

 

[Scotchmo]

I could not locate a verbatim quote stating "cant errors can't happen without drop" but I am almost certain you said that. The above quotes surely seem to indicate that you believe it even if I can't find a specific quote where you stated it.

"...but I am almost certain you said that..."

Keep looking then, and good luck. If you want a statement from me that I actually wrote, you can quote this:

"GUN cant errors do not happen without drop" - Scott Hull

See the difference? If you are getting cant errors without drop, then it is a LOS/scope/reticle cant error. In that case I would refer to it as scope cant.

When tipping the gun about a single aim point, measurable gun cant errors only occur when there is measurable drop, regardless of sight height.