Rifle Scopes scope cant question and thoughts

reewik

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    Ok so there are all these cool tools and gadgets to make the retile level when mounting a scope and several ways people torque and so an and so forth. So lets say you reticle is canted and you zero the rifle with the scope level and continue to shoot with the scope level. In other words, your rifle then becomes canted during this process. Before I continue I understand shooting with a canted scope will cause some undesired hit especially at distance. I understand if you canted to the left, retile wise, that while diling for distance you can hit left of target becuse of scope travel and such. But if you just suck at mounting scopes and you do have a little cant but you are zeroing the rifle with the reticle level and shooting with the rifle level my thought are it should not matter. Are my thoughts on this correct?
     

    dragoon

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    I can't directly answer your question , but I try to eliminate any cant when I install my scopes . I put the scope in the rings/mount and clamp it to an M4 receiver , then use a carpenter's framing square under the receiver , and along the side turret(s) , to mechanically align the scope to the receiver . Then I tighten the rings gradually from side to side , to maintain 'square' . In a quality scope , the reticle should be aligned with the tube/turrets .
     
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    db2000

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    You have to think of the cant on the reticle in relation to the barrel. Both must be level together but separately also.

    If your scope reticle is canted left, while rifle (presumably) is level then you would have to can’t the barrel right to get the scope reticle level.

    Just learn to do it properly. There’s plenty of videos online. Otherwise, buy a Spuhr one piece mount and it comes with a leveling wedge that anyone should be able to use properly. If not you probably have no business shooting a gun. 🍻
     

    KnowNothing256

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    If the scope isn’t leveled to the bore, then you’ll induce unwanted windage error at longer ranges. As the scope is dialed up, it will also dial away from vertical center, and that deviation from plumb increases both with elevation dialed and with cant angle.

    Very minimal cant errors won’t manifest in an error that is discernible in the noise from error due to imperfect wind calls, at least for most shooters. However, it’s an easy issue to minimize, so generally the precision community says: why would you not take a few simple steps to minimize it?
     

    reewik

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    Mine is very minimal as I still hit where I aim, I am not talking about a huge degree of issue here. I am just asking about the theory behind it. Anyone can say just do it right and I get that mounting it right in the first place is the answer but I am not asking for directions or guidence to mount the scope I am talking about the principle of bullet flight right? As far as the barrel , why would that really matter if you are following what I am saying. for example I have an AI with interchangeable barrels with AI mounts and I change calibers when I want to. The barrel is spunn up with a twinst rate not with a twist rate with an index point so why would gun position matter. To expand upon that, you can shoot your pistol sideways like a gangster and still hit poa poi.. My theory is it does not really matter as long as when you shoot your reticle is level on the target every time. This is what I am asking about. Point taken about leveling the scope with the rifle.
     

    Sniperstud

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    Online Training Lesson: Mechanics of a Rifle Cant


    <iframe width="560" height="315" src="https://www.youtube.com/embed/B3ZsCTZOrYM" frameborder="0" allowfullscreen></iframe>


    Use Up/Down Arrow keys to increase or decrease volume.
    Canting your Rifle


    A lot people have read my article on setting up your precision rifle with a small amount cant built in based on the shooter. This serves several purposes, the main is to protect from subconsciously canting the rifle. The body has a natural hold, it will always attempt to default to this natural position which, in many cases induces rifle cant without the shooters knowledge. Because the brain wants the rifle held this way, you will ignore it until the effects compound to an unnatural point. Then you see the shooter correct it, and straighten out the rifle.

    (Link to Leveling your Scope Article )

    Here you can see a small amount of rifle cant with this shooter during a recent precision rifle class. It’s pretty common to see a shooter being slightly canted. The use of levels has made this even easier to see as most don’t pay any attention to them. They look once, straighten the rifle out, go back to lining up the shot, move and never see it.

    Most guys would rather dial in .2 mils left and call it spindrift, true story. [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/SH_HD_CANTLESSON-1-1600x900.jpg"}[/IMG2]Canting the rifle
    When you level the scope and reticle to the rifle and then cant it, you compound the error vs using your natural hold to the brain’s advantage. Levels vs Vestibular System


    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/14297-004-9BE5EEEB.jpg"}[/IMG2]

    So what is more accurate, the $6 level placed in a $100 wrapper or your inner ear ?

    The vestibular system is there to maintain your proper equilibrium. It also works to coordinate the position of the head and it’s relationship to the eyes. So in other words, we have a system within our body to maintain level based on what we see, and the position our head is in. For the shooter you have a more accurate level built into your head. It’s even liquid based.

    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/14296-004-75118A1C.jpg"}[/IMG2]

    Thomas Haugland of the LongRange Norway Vlog has an excellent video comparing this against a highly accurate electronic level. He shows the small vial levels are only about .8 degrees accurate versus the inner which was closer to .2 degrees. Not sure about this, here:


    <iframe width="560" height="315" src="https://www.youtube.com/embed/iChDlTNmk0I" frameborder="0" allowfullscreen></iframe>


    Use Up/Down Arrow keys to increase or decrease volume.
    Training Tools vs Shooting Aid


    I view a level as a training tool versus a shooting aid. We don’t do well trying to watch two things at once, honestly about 90% of the people out there with levels don’t use them at all or correctly. By putting it in the “training” category, you pick up on the clues it is handing you. Clue number one, if every time you do reference the level you are off center, that is a clue telling you to adjust your system to fit you. If you find looking at your level it’s off, your body will subconsciously move it as soon as your attention goes somewhere else like the target.

    For the guys who talk uneven terrain, horizon lines, etc, if your systems is set up to your body, your natural hold, none of that matters. When shooting a target like this, where is my horizon line anyway? The terrain is not only uneven, the horizon is not visible in the scope. The targets do not have straight lines to reference. [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/2014-05-21-15.20.04-3-1600x900.jpg"}[/IMG2]Reticle leveled to the target
    The goal should be to quarter the target, our attention goes to the reticle as that is where our bullet is expected to go. Consider how many people know the shot will be bad before it breaks, this is common. You see the reticle drift off but you fire anyway, the mind says, “Well how bad can it be“… Sniper’s Hide Online Training

    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/Screenshot-2017-08-18-14.24.36.png"}[/IMG2]


    This video is only a small part of our Online Training Lessons located in the Sniper’s Hide Forum. We offer new lessons every month, this month, we did a 10 minute lesson on canting the rifle. The training lessons are not intended to replace a competent instructor, rather they are there to help educate the long range shooter. Our online training section is a private forum, so only guys who want to be there are participating.

    Established in 2009, we have a host of videos on a wide range of topics. We also take specific requests for lessons. Deliberate Canting Data


    The article about leveling your scope to gravity gets referenced a lot, so I want to includes the instructional slides we have to demonstrate the difference between a deliberate cant vs. accidentally canting the rifle as most do. I want to state this set of slides talks about a 2 degree cant, but most shooter’s natural hold is far less than 2 degrees.

    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/Rifle-cant-with-scope-level-explanation-2.001.jpg"}[/IMG2]



    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/Rifle-cant-with-scope-level-explanation-2.002.jpg"}[/IMG2]

    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/Rifle-cant-with-scope-level-explanation-2.003.jpg"}[/IMG2]

    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/Rifle-cant-with-scope-level-explanation-2.004.jpg"}[/IMG2]

    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/www.snipershide.com\/wp-content\/uploads\/2017\/08\/Rifle-cant-with-scope-level-explanation-2.005.jpg"}[/IMG2]

    This is just a small piece of the puzzle there is so much more to explore.

    Muzzle Velocity Variations, Prone vs Bench

    Scope Buying Advice
     

    KnowNothing256

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    Mine is very minimal as I still hit where I aim, I am not talking about a huge degree of issue here. I am just asking about the theory behind it. Anyone can say just do it right and I get that mounting it right in the first place is the answer but I am not asking for directions or guidence to mount the scope I am talking about the principle of bullet flight right? As far as the barrel , why would that really matter if you are following what I am saying. for example I have an AI with interchangeable barrels with AI mounts and I change calibers when I want to. The barrel is spunn up with a twinst rate not with a twist rate with an index point so why would gun position matter. To expand upon that, you can shoot your pistol sideways like a gangster and still hit poa poi.. My theory is it does not really matter as long as when you shoot your reticle is level on the target every time. This is what I am asking about. Point taken about leveling the scope with the rifle.
    It does matter, actually. Even using the pistol example, those sights are typically calibrated for a certain range, held in the vertical. So, just like a rifle, the sights are pointed "down" relative to the straight line of the bore, causing you to need to lift the bore to get the sights on target, which then tosses the bullet "up" at just the right amount for the arcing trajectory to meet the target at the calibrated range.

    However, this angle (where the sights are pointed "down" towards the line of bore, or LOB) has a very different affect on bullet trajectory when you turn the gun sideways. Let's assume we're talking about a right-handed shooter, who has turned the gun in standard "gangtsa" style, with mag well facing right and gun sights on the left. Now the sights aren't pointing down, they're pointing to the right, again to meet the LOB. Which means that if you aim at the target at the proper range, now the bullet will a) impact to the right left of POA, and b) impact below POA, since the sights are no longer causing you to lift the muzzle upwards with respect to gravity.

    Does that explain why cant matters very well? Let me know if I need to clarify anything.
     
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    reewik

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    Thanks JakeM - This is exactly what I mean and thanks for taking your time to post this video. It verifies that I am thinking correctly. I will say that I want to get them perfect but I just do not shoot as much as I used to with everything being thru the roof and hard to find. Gust gives you more time to think is all and fix what you have. LOL
     

    JakeM

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    Thanks JakeM - This is exactly what I mean and thanks for taking your time to post this video. It verifies that I am thinking correctly. I will say that I want to get them perfect but I just do not shoot as much as I used to with everything being thru the roof and hard to find. Gust gives you more time to think is all and fix what you have. LOL
    It will depend on how the rifle fits in your shoulder and whether or not the butt pad is adjustable for can’t. If it is then level the scope to the rifle and adjust the pad to fit your shoulder. If not then fit the rifle to you shoulder and level the scope from there (as long as the rifle cant is a reasonable degree)
     
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    spife7980

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    The TLDR version- level your reticle to gravity while you are comfortable behind the rifle and get to shooting, you wont be able to shoot the difference.

    Via frank
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