Do you adjust sights for cant?

[clickngofar]

Hi Guys,

I shoot mainly air rifle silos, and wondered if my findings regarding sights settings are the same as your:

I've zeroed both scope dials for the chickens, and testing off a bench, simulating the same cant as I used when standing, I found I had to wind on 2 mins of right windage for the pigs, and leave it there for the turkeys and rams.

I would have though I would have needed more correction the further back I went, but this was no what my tests showed.

I'm using a 12 ftb, Air Arms EV2, with JSB exacts, which has proved to be an astonishingly accurate combination.

Anybody done similar tests, and care to share their findings?

Max...Auckland NZ

[ajj]

I know that some people who cant the rifle turn the scope in the rings so that the horizontal crosshair is level when canted.

[clickngofar]

Yeah, I can understand that, but that still wouldn't make any difference to the POI would it?

It would simply be a cosmetic thing, and if you shot  targets or knockdowns, you would have to turn it back again.

[hh4064]

I have always made minor adjustments.... depending on the speed of my ammunition.. std velocity (eley red) chickens dead on, pigs one click, turkeys two clicks and rams three clicks. Try it on paper and see how you fair... If I am shooting fast stuff >1200 fps I will go only two clicks at the rams.. This has worked nicely for for yrs......
good luck
Mike

[dave imas]

i've been accused of canting my rifle on occassion.  it is important that one keeps their cross hairs even with the horizon so any adjustsments for wind have their true value.  initial point of impact should be the same whether you can't or not.  what happens when you adjust could be very different if your cross hairs aren't parallel to the ground.  when shooting a chin gun one had to go over when one went up.  this was due to the height of the scope abobe the barrel and the fact that the scope was usually offset from the vertical centerline of the stock.  but they were WAY up and WAY over...  not allowed in the rules anymore.
dave

[eeleater]

The title you chose is misleading people, because your question does not actually relate to cant.

What you are reporting is a different windage adjustment for chickens vs the other animals.

I suspect what has happened is that at the chicken elvation setting on the scope it is so near the edge of the elevation adjustment range the windage adjustment is affected.

I would suggest:
Optically centering the scope by taking it off the gun, supporting it in two "V's" cut in cardboard and adjusting both elevation and windage so the crosshair or dot stays cented as you rotate the scope in a circle.

Mount the scope to the gun using a mount that allows adjustment for both elevation and windage.  There are several designed to do this with air-rifles.  Adjust the point of impact using the mount only at the TURKEY distance.  After this you can use the scope adjustments to fine tune the turkey settings and get the sight settings for the other animals.

You will find you need to go down for the chickens about as much as you need to go up for the rams.  This sight setting process will keep the scope adjustments where they are most consistent and accurate.

The second best apprach in you situation would be to shim the scope so your current pig setting becomes the chicken setting and you avoid the adjustmen range you have demonstrated to be different.

[clickngofar]

Eleater, thanks for your contibution, but all that seems unnecessarily complicated to me.

All I do is as soon as the chickens are done is simply wind on my windage and I'm good to go for the rest of the match.

It's that simple and it works...well for me anyway.

I have tried to keep my rifle level, but it's too much of an unnatuaral hold for me, and canting allows me to be balanced and comfortable with minimum strain.

I probably need a ballistician to explain what is happening, as I think the mathematics at play here are too complicated for me to understand.
Factors such as pellet speed, range distance, angle of cant, pellet weight, and god knows what else, all have an influence I'm sure.

But the proof of the pudding is in the testing, and that's what I have to take notice of to maximise my hit count.

One never stops learning in this game, does one?

[BillP]

You can adjust a scope for most anything including canting IF you are shooting at a spesific range and something like the wind dosen't change.  That being said, its a BAD idea.  Muscle memory is an important factor in the way we mount and hold a firearm and as they say,"when the chips are down we do as we have trained".  So if you teach yourself to shoot canted you will limit yourself to one spesific shooting sport.  Forget that whitetail hunting trip because when the buck fever kicks in, you will cant your rifle and miss.  The classic methoids of shooting have developed because they hold true under nearly all circumstances.  Rifle silhoutte is a game for "shooters" not "game players".  Why limit yourself to one "game".

[nomad]

BillP,

Could you expand on that just a little?
Maybe some actual, range specific POA/POI deviation with the 5-8 degrees of cant that many silhouette, x-c and international shooters use?

[yankee]

Things that come out of a barrel will go basically straight down no matter which way it is canted.  The horizontal crosshair should be level that way the verticle crosshair will follow the bullet down.  
Yes, I have had some rifles and ammo that need some windage adjustment lets say a click at pigs then no more. Never thought about why just shot them

[dave imas]

i've done a bit of homework over the years and found that many of the classic shooters cant their rifles.  i've canted my rifle for many years with some level of success.  i shot canted in international air rifle, shoot canted in highpower silhouette, shoot canted in smallbore silhouette and, although i don't hunt, the coyote i shot that was eating my sheep was shot with a canted rifle as well.  lets not confuse canting the rifle with canting the scope.  as yankee suggested, crosshairs still need to be aligned properly with the horizon.  and...  with all due respect...  all any of us are doing is playing a game.  if it wasn't a game i wouldn't be doing it.  i've yet to meet somone that is making a living from shooting silhouette.
dave

[clickngofar]

All,
Thanks for your comments.

I'm still struggling to understand why aligning the crosshairs to the horizon is so important.
Is it simply because you can get better repeatability, whereby you can tell by any misalignment, that you're holding at a different angle?
Or are there other reasons?

If you have done tests, what have you found?

I also have no problem with having a set of click adjustments for a specific discipline.
It would be silly not to.
If I hold my rifle a different way from standing to prone, I want to know beforehand what I have to do to correct the change it's going to have on my P.O.I.

Forewarned is forearmed...so to speak.

[CB]

If the cross hairs are + or straight up when you fire, then theorectically turning the elevation up should result in a straight up movement. If however the crosshairs are X when you fire then an up adjustment will in reality move point of  impact up and to the left requiring right windage at the same time to get straight up adjustment. comprende?
Carroll

[1armoured]

There seems to be some confusion regarding the effects of cant.

I won't try and give my own understanding of the problem,

but sight settings definitely need to be adjusted, proportionate to the angle of cant, the height of the scope above the action, and the distance to the target.

Here is an article from 'Varmint Hunter' that sums it all up.

There are a number of other articles on the web that explain.

Some of them a bit more technical than others.

http://www.microlevel.biz/cant_errors.html

I guess the idea is to cant as little as possible,

although I have to cant a little to get a comfortable position with the non-adjustable sporting silhouette rifle stocks that I use.
I align the cross-hairs with the horizon so that my cant is always constant.

I then check POA at each distance, and adjust accordingly, when shooting a match.

I notice it most out at 500mtrs with the .308 and a reasonably high-mounted scope.

Sean in 'Godzone'

[dave imas]

Hi Sean,

question...  when you cant... are your cross hairs canted as well or do you cant your rifle and keep your horizontal cross hair parallel with the horizon?

[1armoured]

Hey Dave,

My rifle is canted so that the buttpad fits comfortably into my shoulder, and I get good alignment of scope to eye.

I then align the scope in the rings, so that my crosshairs are aligned to the horizon, when the rifle is canted on my shoulder.

Both for 'sight picture,... and also it gives me a check that I am using a consistent angle of cant when my crosshairs are correctly aligned.

cheers,
Sean

[dave imas]

Thanks Sean.   that is what i do as well.  allows me to be sure i have my back in the correct position and my center of gravity where it belongs.
dave

[1armoured]

Me too Dave,

being right handed, I'm leaning backwards, and my hi-mounted scope/rifle combo is canting to the left, to enable me to keep my head up, but I still see a level cross-hair.

This backward curve to the back keeps the weight/balance better centred, and helps prevent the body's tendency to fall forward with the imbalance you've just added.

And, you can't go backwards because your spine 'don't go there' !

Here's a good description of an ideal standing position by Target Shooting, Canada.

http://www.targetshooting.ca/reframerize.cfm?redirect=http://www.targetshooting.ca/train_r_stand.htm

and the US of A version, with picture, (although his head is leaning over a little too much for my liking , but then it's an apperture sight !)

http://www.smallbore.us/readarticle.php?article_id=6

cheers,
Sean

[B_Koes]

BillP,

Could you expand on that just a little?
Maybe some actual, range specific POA/POI deviation with the 5-8 degrees of cant that many silhouette, x-c and international shooters use?

Nomad,

Let me step in a bit here.  I took a trip in the way back machine to my high school trig class and figured the effect of cant on a zero.  The formula is really pretty simple to figure the amount of scope offset with the bore.  You can calculate the offset by multiplying the scope height (as measured from center of the bore to the center of the scope) with the tangent of the angle of cant.  Should look something like this...

height * tan( cant angle ) = scope offset from bore

Then I just assumed 100 yard sight-in....

3 degree cant on a rifle sighted in at 100 yards
-.079" @ muzzle  (either left or right depending on the direction of cant)
0 @ 100 yards (sight-in distance)
.079" @ 200 yards
.158" @ 300 yards
.237" @ 400 yards
.316" @ 500 yards

10 degree cant (similar suppositions)
-.264" @ muzzle
0 @ 100 yards
.264" @ 200 yards
.528" @ 300 yards
.792" @ 400 yards
1.056" @ 500 yards

Given the fact that these amounts are less than the inherent wobble of the standing position, I doubt that anyone would ever notice the difference...especially when wind drift comes into play.