Why do people still mount scopes the way they do?

ken226

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How canted the rifle needs to be to comfortably fit MY "natural point of aim" tends to be a little different in difference circumstances. Prone tends to be a little different than sitting, kneeling, off a tripod or when shooting from sloped ground on a mountainside. I don't have a public range nearby, so do all of my shooting up in the North Cascades.

So, I just split the difference and level the bottom of the scope body to the pic rail. I don't give a shit if it's not perfect. The magnitude of any error due to a fractional degree of cant, is usually alot less than the accuracy of my wind calls and range estimation anyway.

Perhaps some shoot to such a higher level of precision that it needs to be perfect, but to me it's just not a big enough deal to give a shit about.
 
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phlegethon

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    Anytime you add slope to a rail or mount, you no longer have the bore of the rifle, and the scope in parallel. If you induce cant to the equation, then you have the bullets flight path travelling at an angle (azimuth plane) away from your target.
    The optical axis and the bore are never parallel regardless of how you mount the scope. They only would be if you had a projectile that wasn't affected by gravity.
     

    Precision Underground

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  • Anytime you add slope to a rail or mount, you no longer have the bore of the rifle, and the scope in parallel. If you induce cant to the equation, then you have the bullets flight path travelling at an angle (azimuth plane) away from your target.
    I can’t imagine how adding vertical offset would change anything in this scenario as long as the reticle is level. Maybe I’m wrong but I can’t see it. @Rocketmandb what say you?
     

    Charger442

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    The optical axis and the bore are never parallel regardless of how you mount the scope. They only would be if you had a projectile that wasn't affected by gravity.

    alpine's point is you now have a scope rail that cants in two directions, instead of in the vertical plane only.
     

    Mike Casselton

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    Well gorsh, let’s see now. Earlier in the week I took my NIB LRHS2 down to the range where a couple good friends shoot, so they and I could compare it with the LRHSi that was already mounted on my heavy Valkyrie AR.

    When it was time to swap optics, I placed the rifle on a bench, held up by a bag and bipod. Removed the scope ring caps, took out the old scope, put the new scope in, replaced the ring caps and got prone to adjust eye position and reticle level according to being behind the rifle. With all of that highly technical stuff out of the way, I tightened the ring screws and proceeded to set zero.

    I’m pretty sure I could have done it correctly if I had watched half a dozen YouTube how to videos and bought some high end fixtures, but I’m just funny like that.

    It looked way crooked to me. 🤣🤣

    Good thing the turrets are reliable. 😉
     
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  • alpine's point is you now have a scope rail that cants in two directions, instead of in the vertical plane only.
    But if the reticle is level any dialed elevation is still true. You’re still starting from zero whether the scope has elevation offset or not..... I think. I’ll let one of our resident engineers answer.
     

    Charger442

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    But if the reticle is level any dialed elevation is still true. You’re still starting from zero whether the scope has elevation offset or not..... I think. I’ll let one of our resident engineers answer.

    as long as you compensate for it.

    with your reticle level to the ground, with rifle canted and 20 moa rail, has your reticle cross hairs being pulled down toward the bore of the rifle, which is then in both the y and x axis of the real world, not JUST in the Y axis if it was directly over centerline of the bore.

    in reality, you scope then has a certain MOA of cant in the vertical axis and a certain amount in the X axis. if you zero that way, i think there would be an effect on your windage call and your elevation dialing, but im not going to sit down to do the math and figure it out.
     
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  • as long as you compensate for it.

    with your reticle level to the ground, with rifle canted and 20 moa rail, has your reticle cross hairs being pulled down toward the bore of the rifle, which is then in both the y and x axis of the real world, not JUST in the Y axis if it was directly over centerline of the bore.

    in reality, you scope then has a certain MOA of cant in the vertical axis and a certain amount in the X axis. if you zero that way, i think there would be an effect on your windage call and your elevation dialing, but im not going to sit down to do the math and figure it out.
    But the error is still the same as illustrated by Frank above. It’s extremely negligible. Large errors happen when the reticle is not level and you dial seven mills up. In that case you’re dialing up and over depending on how much the reticle is canted. The scope being slightly off the bore axis has been calculated and is negligible. If you were shooting bench rest you may want to go down that rabbit hole. For tactical shooting a comfortable, consistent hold on the rifle is much more important.
     

    Schütze

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    I learned a long time ago to never ever argue with an engineer lol, actually the truth. It was in my time working in professional racing ( cars).
    We did win numerous times anyway working against their advice. And then Monday morning came the phone call, how did you do it?
     
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    Charger442

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    But the error is still the same as illustrated by Frank above. It’s extremely negligible. Large errors happen when the reticle is not level and you dial seven mills up. In that case you’re dialing up and over depending on how much the reticle is canted. The scope being slightly off the bore axis has been calculated and is negligible. If you were shooting bench rest you may want to go down that rabbit hole. For tactical shooting a comfortable, consistent hold on the rifle is much more important.

    thats right, you should still be able to push through the error. but we're on a site where people are lapping the front of their upper receivers on gas guns chasing accuracy. lets not pretend we dont (as a group) care about fractions of an inch. :ROFLMAO:
     
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  • thats right, you should still be able to push through the error. but we're on a site where people are lapping the front of their upper receivers on gas guns chasing accuracy. lets not pretend we dont (as a group) care about fractions of an inch. :ROFLMAO:
    Exactly. That was the whole point of me posting here; to convey that worrying about a level rifle to save .66” at 1000 yards is futile. Guys are trying to set up a rifle and then mold themselves to it rather than setting themselves up and molding the rifle to their body. The latter leads to consistency that will erase/offset well more than .66” @ 1000.
     
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  • I learned a long time ago to never ever argue with an engineer lol, actually the truth. It was in my time working in professional racing ( cars).
    We did win numerous times anyway working against their advice. And then Monday morning came the phone call, how did you do it?
    Lol, classic engineer(no offense to some engineers here).
     

    308pirate

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    as long as you compensate for it.

    with your reticle level to the ground, with rifle canted and 20 moa rail, has your reticle cross hairs being pulled down toward the bore of the rifle, which is then in both the y and x axis of the real world, not JUST in the Y axis if it was directly over centerline of the bore.

    in reality, you scope then has a certain MOA of cant in the vertical axis and a certain amount in the X axis. if you zero that way, i think there would be an effect on your windage call and your elevation dialing, but im not going to sit down to do the math and figure it out.
    The reticle is "canted" fore and aft even without a canted scope mount. How the fuck do you think a rifle is zeroed?
     

    lash

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    Yeah, but put a 20-moa rail or mount on the rifle, and the above goes out the window.

    Anytime you add slope to a rail or mount, you no longer have the bore of the rifle, and the scope in parallel. If you induce cant to the equation, then you have the bullets flight path travelling at an angle (azimuth plane) away from your target.
    Do the math and show us how wrong we are, or actually how much it doesn’t matter. Most people want to argue with the canted rifle canted reticle even when you show them the math. I’d bet that most of you didn’t actually read the article that Frank wrote and Snipe posted. Too complicated.

    It’s easier just to believe what you want to believe.

    But I’m serious, show us the math or you’re just talking out your ass.
     
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    carbonbased

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    As alluded to earlier, when mounting scopes, I used to FUCKING SWEAT THE DETAILS. Twiddle this, twaddle that, FUCK I DIDN'T DEGREASE MY BALLS! Etc etc etc etc etc

    After I Stopped Worrying And Learned To Love The Bomb I mounted scopes like I used to mount girlfriends. Fast, rough, hard. Spanking was involved.

    Wives, well…thing change. Not always for the better. But I always seem to have more scopes to “mount.”

    (I’m grossing myself out here)

    1627065592031.jpeg
     
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    Rob01

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    I only shoot out to 799 yards
    Must be shooting a .308 as we all know they drop out of the sky at 800 yards.

    This thread is great. About as fun as the thread with the guys loading their .22s down with tons of weights to get that perfect balance on a pin point in front of the magwell, that we all know is completely needed to hit anything :rolleyes:, and ending with 20+ pound .22s. LOL
     

    JakeM

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    Must be shooting a .308 as we all know they drop out of the sky at 800 yards.

    This thread is great. About as fun as the thread with the guys loading their .22s down with tons of weights to get that perfect balance on a pin point in front of the magwell, that we all know is completely needed to hit anything :rolleyes:, and ending with 20+ pound .22s. LOL
    The funny thing is. The people weighing down their guns, are the same people saying that the gen 2 razor is too heavy.
     

    Alpine 338

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    Do the math and show us how wrong we are, or actually how much it doesn’t matter. Most people want to argue with the canted rifle canted reticle even when you show them the math. I’d bet that most of you didn’t actually read the article that Frank wrote and Snipe posted. Too complicated.

    It’s easier just to believe what you want to believe.

    But I’m serious, show us the math or you’re just talking out your ass.


    Ok, I'll help you get started with the math...

    I will use real world examples;

    Caliber: 338LM, 375CT, etc, something capable past 2000-yards.

    My 338LM rifle: 20-moa rail, 25-moa scope mount, with a total of 45-moa which allows full use of a S&B 5-25 elevation travel.

    1-moa is 1.047" at 100-yards.
    1-moa is 20.94" at 2000-yards.
    45-moa is 942.3" at 2000-yards.

    942" is a big distance in the ELR realm of things, unless that's the size of the target you're shooting at., Then you might get lucky and hit it being that big with all the induced error you want to ignore. Granted, you won't have the full 942" error unless you cant you're rifle at 90-deg. But some people think a 15-deg cant is acceptable.

    That's a start, I'll let you clowns continue with the math class based on you acceptable rifle cant as I don't have time to get into Sin, angle errors, etc.
     
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    lash

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    Ok, I'll help you get started with the math...

    I will use real world examples;

    Caliber: 338LM, 375CT, etc, something capable past 2000-yards.

    My 338LM rifle: 20-moa rail, 25-moa scope mount, with a total of 45-moa which allows full use of a S&B 5-25 elevation travel.

    1-moa is 1.047" at 100-yards.
    1-moa is 20.94" at 2000-yards.
    45-moa is 942.3" at 2000-yards.

    942" is a big distance in the ELR realm of things, unless that's the size of the target you're shooting at., Then you might get lucky and hit it being that big with all the induced error you want to ignore.

    That's a start, I'll let you clowns continue with the math class as I don't have time to get into Sin, angle errors, etc.
    Lolol! You’re a funny guy. That wasn’t math genius. I didn’t say that I wanted to do the math, I called you out and said that your full of hogwash unless you do that math to show us otherwise. Those were just drops from your ballistic app. I hope that didn’t stress you out to much or take too much of your time.

    Ive got time…I’ll wait.

    ETA: oh yeah. You’re changing your story too. You originally said that adding a standard 20moa rail would throw this all for a loop. Funny that real world applications that people do every damn day don’t bear out your unsupported theory.
     
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    Alpine 338

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    Lolol! You’re a funny guy. That wasn’t math genius. I didn’t say that I wanted to do the math, I called you out and said that your full of hogwash unless you do that math to show us otherwise. Those were just drops from your ballistic app. I hope that didn’t stress you out to much or take too much of your time.

    Ive got time…I’ll wait.

    ETA: oh yeah. You’re changing your story too. You originally said that adding a standard 20moa rail would throw this all for a loop. Funny that in real world applications that people do every damn day don’t bear out your unsupported theory.

    No, that was my smart phone calculator as everyone knows 1-moa is 1.047" at 100-yards. Simple math (multiplication).

    If I have time later, I'll do the rest of the equation, maybe Bryan Litz will step in and solve the simple math problem for you before I return.
     

    Winny94

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    Hmmm . . . seems like a gun vice (or other good rest) with the gun in it and a level on the pic rail gets you to exactly the same place as the first overpriced device, and you will know it fits correctly as well . . . . You can then level to a plumb nob (or whatever) or use something like a Wheeler scope level to true it to the rail.

    ???
    this isnt exactly the most fiscally responsible hobby haha. People spending hundreds, if not thousands for perceived advantages they may never realize.
     

    TurboTrout

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    Eye relief would be why I wouldn’t final mount the scope to rings than rings to rifle.

    Leveling isn’t that big of a deal, and my scope and rifle become one once it’s installed, same reason I don’t care for quick detach stuff for my optics.

     
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    Im2bent

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    As alluded to earlier, when mounting scopes, I used to FUCKING SWEAT THE DETAILS. Twiddle this, twaddle that, FUCK I DIDN'T DEGREASE MY BALLS! Etc etc etc etc etc

    After I Stopped Worrying And Learned To Love The Bomb I mounted scopes like I used to mount girlfriends. Fast, rough, hard. Spanking was involved.

    Wives, well…thing change. Not always for the better. But I always seem to have more scopes to “mount.”

    (I’m grossing myself out here)

    View attachment 7673380
    Best thing for de-greasing your balls is 90% IPA works like a charm.
     

    Gil P.

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    As it would pertain to 1pc mounts specifically.



    Just mounting it in the ring setup, off of the gun, then put the entire assembly on the pic rail?

    Seems like you're fighting 2 battles trying to level the gun and the scope.

    Why isn't it common practice to put the ring/mount setup on a known, flat surface then just install and level the scope in the mount/ring setup? Short of some major mfg defects, the pic rail on the gun will be absurdly flat.

    Because the pic rail on your rifle may not be flat/straight. Mounting your scope and rings on the rifle helps alleviate stresses placed on the scope.
     

    Rocketmandb

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    I can’t imagine how adding vertical offset would change anything in this scenario as long as the reticle is level. Maybe I’m wrong but I can’t see it. @Rocketmandb what say you?

    My head hurts after reading this thread. However, I will say that anyone who thinks that adding a sloped mount does anything to the equation doesn't understand what's happening inside a scope when you dial for elevation.
     

    Gil P.

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    Just an unnecessary super OCD thought, all the latest cameras I have purchased have electronic pitch and yaw indicators.
    Phones and iPad have these as well as accelerometers.
    Shrug, just put them into scopes, walla, super sensitive over the top expensive unnecessary diagnostics that measures your breathing??
    The Steiner M7Xi 4-28x56 with ifs has this.
     
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    Snuby642

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    You learn to use the tools you have avalable to the extent of thier capabilities.
     
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