Here's a great video showing the effects of rifle cant.
Priceless video on rifle cant.
- Thread starter Airgun-hobbyist
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Thankyou ,WOW i have tried to explain this to a lot of people . I have even placed a level on their rifle , they look at the level @ 0 then look through the scope and i watch them cant the gun then shoot . miss
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The first thing that I do to any scope, even before mounting on a rifle, is to align the cross hairs to a weighted plumb line and install a permenant bubble level.
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I learned a great lesson regarding scope cant while camping this Fall. I set my shooting table up at camp and was on a slight slope. Not a great slope that was totally obvious but it was there. I was shooting at 110 yards at some steel. Looking through the scope the crosshairs appeared level. I guess your mind and eyes try to compensate for the slope of the bench set up. Anyway, I’m hitting about two inches right and about an inch low. After a few shots the problem occurs to me. I get out my bubble levels that screw into the Eagle Vision scope rings. Now with the bubble levels set correctly the cross hairs look to be slanted but I know they are level. The next shot at 110 yard is right on target. I know better and should have started out with the levels installed. I try to always use those levels when shooting and hunting. Great lesson in physics.
When initially setting up any scope I like to use the Wheeler tool to get everything aligned and then I’ll set up a plumb line to double check.
Kenny
When initially setting up any scope I like to use the Wheeler tool to get everything aligned and then I’ll set up a plumb line to double check.
Kenny
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Projectiles (theoretically) fall in line with gravity. If your vertical crosshair isn't in line with gravity it's at an angle to the flight of the pellet. The farther down the crosshair you go the greater error you will have.
It's relatively unimportant if you shoot off the crosshair and the scope is plumb with the bore. A little cant won't make (much) difference. If your shooting with a lot of holdover and cant the rifle (or the scope is not plumb with the bore) it can make a lot of difference. The farther the pellet travels the more it matters.
Even if you click to zero you will get some error if your scope is not optically centered. And some scopes travel is not in line with the vertical crosshair. There are a lot of variables that compound each other at range. Any alignment problem no matter how small can affect POI. That's why it's important to mount your scope as precisely as possible and pay attention to cant in your shooting routine.
Mount your gun in a stable rest, level it and sight it on a distant light on the horizon. Turn your elevation turret up all the way and then down all the way. The light should track along the vertical crosshair. If it does not track perfectly something is out of alignment.
Shoot a tall target at 25 yards. 3 dots. One at the top of a 36" target. One in the middle. One at the bottom. Zero the crosshair on the middle dot. Shoot at the bottom target using your bottom mil dot (or duplex). Shoot at the top target off the upper mil dot (or duplex). If you have windage difference between the 3 patterns something is off.
A level works fine for targets if it is level and everything else is lined up. But if the scope is a couple degrees off, your optical center is off and the crosshairs aren't plumb with the bore it's moot. You will still shoot a little off at distance unless you eliminate all the variables.
The tall target or tracking a light on the horizon is the only way you know for sure that your holdover isn't introducing a windage error. When the scope tracks perfectly plumb your gun level should be adjusted to match. Otherwise your level will be compounding a cant error rather than eliminating it.
It's relatively unimportant if you shoot off the crosshair and the scope is plumb with the bore. A little cant won't make (much) difference. If your shooting with a lot of holdover and cant the rifle (or the scope is not plumb with the bore) it can make a lot of difference. The farther the pellet travels the more it matters.
Even if you click to zero you will get some error if your scope is not optically centered. And some scopes travel is not in line with the vertical crosshair. There are a lot of variables that compound each other at range. Any alignment problem no matter how small can affect POI. That's why it's important to mount your scope as precisely as possible and pay attention to cant in your shooting routine.
Mount your gun in a stable rest, level it and sight it on a distant light on the horizon. Turn your elevation turret up all the way and then down all the way. The light should track along the vertical crosshair. If it does not track perfectly something is out of alignment.
Shoot a tall target at 25 yards. 3 dots. One at the top of a 36" target. One in the middle. One at the bottom. Zero the crosshair on the middle dot. Shoot at the bottom target using your bottom mil dot (or duplex). Shoot at the top target off the upper mil dot (or duplex). If you have windage difference between the 3 patterns something is off.
A level works fine for targets if it is level and everything else is lined up. But if the scope is a couple degrees off, your optical center is off and the crosshairs aren't plumb with the bore it's moot. You will still shoot a little off at distance unless you eliminate all the variables.
The tall target or tracking a light on the horizon is the only way you know for sure that your holdover isn't introducing a windage error. When the scope tracks perfectly plumb your gun level should be adjusted to match. Otherwise your level will be compounding a cant error rather than eliminating it.
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Great video & explanation. Glad I realized when first starting out how important plumb mounting of scope is, mounting exterior scope level accurately AND working on technique while shooting to keep all things in line.
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The girl from AOA made a video on cant that is much easier to understand, and yes cant is a major issue, when shooting pellet rifles at long distances.
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You can fuss with scope alignment for hours trying to get it all perfect. You have to if every shot counts.
I adjust for alignment issues by plopping a pellet in the dirt and aiming accordingly. If Im a little left at range I just hold a little right. I'm going to need to account for wind and that is a huge wild card. I'm usually holding a little left or right past 50 yards anyway. I'm happy with a close miss on a transition. I will hit it the next shot.
That first shot is your best guess. In a match they guess right almost every time and that's an incredible feat of skill, knowledge and time invested.
Plinking dispenses with (most of ) those details. You can still hit a target every time but it might take a shot or two to find it. Things like cant and bore alignment become much less important. If a close miss once in a while dosent bother you it's not really that important at all.
I adjust for alignment issues by plopping a pellet in the dirt and aiming accordingly. If Im a little left at range I just hold a little right. I'm going to need to account for wind and that is a huge wild card. I'm usually holding a little left or right past 50 yards anyway. I'm happy with a close miss on a transition. I will hit it the next shot.
That first shot is your best guess. In a match they guess right almost every time and that's an incredible feat of skill, knowledge and time invested.
Plinking dispenses with (most of ) those details. You can still hit a target every time but it might take a shot or two to find it. Things like cant and bore alignment become much less important. If a close miss once in a while dosent bother you it's not really that important at all.
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level the rifle then level scope to the rifle , then hang a plumb line in front of a mirror and look through the scope if that line is on the vertical scope recital AND the plumb line intersects the center of the bore then everything is good
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I enjoyed that video. Thanks.
I might save that for the people that say cant doesn’t matter.
I might save that for the people that say cant doesn’t matter.
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its not only about target shooting, its also when pesting and hunting for the freezer tooIn the Field Target game ... We Live or Die by accurate D.O.P.E. and shooting LEVEL
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