# Rifle cant, and the effect on accuracy



## RobaloSunrise (Jun 10, 2011)

Here is a good article on what happens when you hold your rifle at a angle (cant). It can be pretty extreme.

http://www.accurateshooter.com/optics/canting-effect-on-point-of-impact/

V/R
J


----------



## Longshot270 (Aug 5, 2011)

That is a cool article.


----------



## wtc3 (Aug 16, 2005)

Pretty cool write up. Thanks for posting that.


----------



## woods (Dec 3, 2011)

When Bryan Litz talks about a 1 degree cant or an 8 degree cant, many do not realize how little this is. A 6 degree cant is equal to 1 minute on the clock face and an 8 degree cant is a little over 1 1/2 minutes on the clock face. That is because 90 degrees moves the clock hand to 3 o'clock. In my experience it is hard to visually discern a cant of less than 1 1/2 minutes on the clock face.

What is most important by far is that you shoot when the reticle is level. Your rifle can be canted such as here in Tubbs' cheek-over rifle










but he shot with the reticle level.

For me I find it easiest to take the cant out of the rifle, level the reticle, install an anti-cant device and then shoot with the anti-cant leveling the reticle. When I got the process down I discovered that I naturally held a rifle with a little cant but with a little practice I was able to correct that.

Seemed to improve groups at 600 yds but there are so many factors involved that it is hard to say for sure


----------



## pg542 (Oct 9, 2006)

Very informative....Thanks. This article should be an indicator of how important it is to get your scope(elevation) reticle perfectly level with the gun when mounting a new (different) one. There are tools to help you do this from Midway, Brownells, Wheeler etc. You would be surprised how many scopes I've looked through which were visibly not level. You can still zero a rifle with an unlevel scope, but at any other distances than what it was zeroed at, accuracy can suffer. Probably to a similar degree as what was mentioned in the article when referring to the amount or degree of rifle hold cant. An anti-cant level device cannot work properly if the scope isn't level to the gun, when shooting at multiple ranges. At least that's my way of thinking.


----------



## RobaloSunrise (Jun 10, 2011)

It's not about getting your scope right. It's about knowing that cant changes your POI and you need to maintain the same cant through your shot string. If everything is level to start with it makes it easier for most however there are some who use cant as a way to counter effects of wind.


V/R
J


----------



## woods (Dec 3, 2011)

The trick is to get a rifle set up *uncanted*. There are bubbles out there like the level-level-level but the problem with those is that they are insubstantial, not necessarily manufactured level and it can be difficult to find good surfaces on the rifle and scope to use them. The top of the elevation turret is not always manufactured level with the reticle










A boresighter doesn't work cause you can rotate your scope in the rings to align the vertical in the boresighter and the reticle even if the rifle is canted.

So when is the rifle uncanted? To me it is when the bore of the rifle and the bore of the scope are aligned on a vertical line. For that I use the EXD device and a distant vertical or horizontal object

http://www.brownells.com/.aspx/pid=6097/Product/EXD-ENGINEERING-VERTICAL-RETICLE-INSTRUMENT

http://www.riflescopelevel.com/vertical_retical_instrument.html










the EXD is well made and mine was level with a larger carpenter's level


















and the vertical component fits tight in a groove so it stays level










The way it works is to set your rifle in a vise and place the vees on the barrel and the scope barrel










I aim mine out the door from the bench vise to a 4' level on a fence 30 yds out. When the EXD is level and your scope is locked down with the reticle level with the distant object, your reticle is level when the rifle is uncanted.

This is the best time to install an anti-cant device. I prefer the ScopLevel

http://www.scopelevel.com/content/product_info.asp

Since it folds down when not in use










so I don't have to lose my cheek weld to use it and it doesn't stick out to the side to catch brush or break in a gun case.

There are other ways to accomplish the same thing but this always works for me


----------



## pg542 (Oct 9, 2006)

woods said:


> The trick is to get a rifle set up *uncanted*.
> 
> So when is the rifle uncanted? To me it is when the bore of the rifle and the bore of the scope are aligned on a vertical line.


 ....exactly..This was the point I was trying to make. You just worded it better.lol..................as far as someone using a canted hold to adjust for wind drift...That seems as though that would cause problems, because not only does rifle cant affect windage, it affects elevation as shown in the OP's target POI diagrams. It seems to me a shooter( or me at least) would want to adjust for wind drift and distance starting with an uncanted hold with an uncanted scope and adjust for the conditions at hand. Wind drift can do strange things to a bullet. All else being equal,a left to right wind will not do the same thing as right to left wind due to bullet spin being acted on by the lateral wind. As it was explained to me,with a RH twist bullet, the POI will tend to rise and impact left with a right to left wind and vice versa. As with most things "downrange" related, this affect is only compounded as the range distance increases....now I'm confusing myself...Do the solunar tables affect accuracy?...j/k...lotta good points on this thread.


----------

