Scope rotation question

[Dean2]

Originally Posted by Heyupduck

If my target is vertical (true) line 50yds away
I dial in the turret to max elevation and hit the line
I then dial in the turret to min elevation, but my shots are 1/2" off to the right which way does my scope have to be rotated? clockwise, or counter clockwise?
(from the view of the shooter behind the gun)

I can calculate how many degrees it has to turn, and I can calculate how much difference it needs to move on the circumference, but I just can't seem to get my head around which way the scope has to go.

I think/guess it has to turn clockwise, but want to be sure.

Thanks in advacne

After reading some of the responses I couldn't read all the way through. What you are asking seems pretty clear to me. If your hitting to the right as you move your vertical from top of range to bottom then you need to rotate your scope left.

Think of it this way, your barrel does not move in relation to the scope of cross hair, therefore the cross hair must be moving away from being centred on the barrel. For the shots to be landing right of the line at the bottom, the cross hair must be on a spot left of where the barrel is lined up to. This means as you drop elevation the + is drifting slightly left, which means the bottom of your vertical crosshair is left of center. Rotating the scope left will rotate the bottom of the crosshair right and remove that drift.

[Jordan Smith]

What scope are you using? IF your scope tracks perfectly straight, then you need to rotate your scope counter-clockwise. There’s a good chance, however, that the erector’s tracking may be off, so you’ve got to isolate one variable at a time. Square the reticle up to the rifle using feeler gauges if using a pic rail, or a plumb bob or ReticleTru if using some other scope mount system. Then once you know the scope is square to the rifle, you can test your scope’s tracking to see if it tracks in a straight line or not. You can also use a magnetic bore sighter with an optical grid pattern to observe tracking behaviour of a scope.

[tchardy1972]

Originally Posted by Jordan Smith

What scope are you using? IF your scope tracks perfectly straight, then you need to rotate your scope counter-clockwise. There’s a good chance, however, that the erector’s tracking may be off, so you’ve got to isolate one variable at a time. Square the reticle up to the rifle using feeler gauges if using a pic rail, or a plumb bob or ReticleTru if using some other scope mount system. Then once you know the scope is square to the rifle, you can test your scope’s tracking to see if it tracks in a straight line or not. You can also use a magnetic bore sighter with an optical grid pattern to observe tracking behaviour of a scope.

My thoughts as well. If the scope stayed on the line from zero till the upper stop but tracks left at the bottom stop your looking at a scope problem.

[EZM]

Originally Posted by obsessed1

Scope cant is huge when shooting long range. A three degree cant will equate to 4-5 feet of horizontal error at 1500 yds depending on the round you use.

Most shooters shoulder the rifle and "level" the scope based on what it looks like, while this if fine for 100-300yd shots your "Level" scope is not likely true because of slight cant while holding the rifle.

Good info ... yeah that makes sense

Having the initial set up levelled and mounted properly is definitely important.

I understand the principle and definitely see that being a bigger issue the further you go down range. It definitely something for the BR or competition guy to consider.

Like most guys, I'm happy shooting sub-moa at 100 and happy when grouping 3"-5" at 300.

I'm also not taking many 300+ yard shots unless the shot is something I know I can make.

Sighting in is done with a bench/rest almost exclusively - which should/would ensure a better result when zeroing your scope.