Home Forums Hunting & Shooting Ask The Gunwriters SCOPE LEVELING QUESTION

Good post.

Rick,

Apparently you misunderstand the level of precision at which the tool works, since you've never used one. Yes, it is all "eyeballing," but the eyeballing results in far more precision.

One of the nice things about turkey hunting is that it does not require a whole lot of precision. For a couple of months out of the year I don't have to think with precise logic. Riding around in a truck with a dog hanging out the window is about as complex as it gets. Blowing a turkey's head off with a 12 GA is easy at 15 yards.

However, I'll try and get back into a more sophisticated frame of mind and venture a guess as to how this was done. The picture shows the matrix grid of the bore sighter in such a way that the scope is cranked to near-minimum power. Second, the black margin in the left of the pic indicates the camera is not dead on to the scope.

I know for a fact that if I use my bore sighter with the scope at its minimum power, the ability to align it properly is attenuated. On a 3-9X scope I usually do the work at 6 power or so. There is a slight ( it may be my imagination) misalignment of the horizontal crosshair to the bore sighter such that the right side is up a bit. My guess is that if you were to set the scope to a higher power, that misalignment would be more pronounced.

In regards to the black margin, I know for a fact that you must have your eye centered in the scope and seeing the full view in order to bore sight successfully. This takes quite a bit of work. I put my rifle in a vise and then screw my cheek down to the stock in as close to the final position for shooting as I can. I even arranged my gunsmithing bench so that I could accomplish this. If my eye is not aligned properly to the scope I either do not see the full view (too far back) or a black margin in one quadrant or the other (eye not on center).

Therefore, without making the trip back home and testing it, I would say that Shrapnel has committed two no-nos with his bore sighter.

1) He's not using optimal magnification
2) He's taken the picture from a position that does not match where his eye should be.

The only other thing I can suppose is that his boresighter has an extra adjustment to roll the grid that my cheap BSA does not have.

My brain is aching. The thrust into complexity was too much for it. I'm going back out to scout, and after that, I'm going into town and let both dogs hang out the window and bark at the cows. I may bark at them as well.

Bsa1917douche: I shoot more in a week than you do all year. Here is the Innovative Technologies level at work a few days ago when shooting 1100 yds...

Here is another gun getting levels adjusted for a tall target test. (Note scope level does not match gun level yet). Innovative level on gun, level on scope, reticle verified on vertical line.

WHY?

Let's just say,for example, that I am shooting my 260 Rem with a 120 A-max at 2900 fps. And let's say that I mounted the 10X Super Sniper with a 1/10 degree cant with the right side of the reticle low.

Next, I meticulously align the scope reticle to the target frame and zero the rifle at 300 yds. Then I move to the 1000 yd target. Again, I have a vertical side to the target frame, and am able to level the scope. But obviously the rifle must be canted 1/10 of a degree.

This puts the scope out of vertical alignment with the barrel by some 1/1000ths of an inch.

I am not handy enough with the trig to figure the induced error, but my guess is a couple tenths of an inch from a 300 yd zero to a 1000 yd target.

For the past fifty-plus years, I have been mounting scopes and leveling them by locking at the world through the scope. If they look level, I tighten up the screws. If they look canted, I twist them a little and then tighten up the screws. I do the same whether the rifle is a hunting rifle, an "F" class, BR, or silohuette rifle. The "F" class rifles are fired from 300M to 900M and I've not had any real surprises on the target which could be attributed to anything other than my inability to recognize a change in the wind speed or direction. GD

That pretty well describes my method too. It works well enough that my 100 yard zero's check out pretty near perfect at 200 yards and has allowed me to hit woodchucks pretty consistently out to 300. I have no need nor even a place to take shots farther than that so all is well in my world. I'm thankful I don't need to dick around and stress out over whether my scope is dead nuts perfectly level or not.

Silly bugger!

Everyone knows Tikkas don't shoot!

They're only good to a mile or so, then accuracy falls off.

If a scope is mounted purposely canted or turned in the rings (turned in the rings even a tiny, possible unperceived amount), in a ZERO WIND SITUATION the impacts at various ranges will progressively be right or left (depending on which way the scope is turned in the rings ) and low.

This gives the wrong feedback to the shooter, giving the illusion of wind effect that isn't there.

For most shooters who are ignorant of this and who don't require the precision to benefit from a good scope mount, it doesn't matter.

If the scope is mounted canted in relation to the rifle but the shooter cant the rifle so that the scope is level the point of impact will be reasonably consistent as far as windage is concerned. If, for instance, the scope ends up offset by 1/8inch (fairly extreme)and the rifle is sighted to hit center at 100 yds, it will be 1 1/8 inches off at one thousand. Since most rifles don't shoot well enough to see 1/8 moa at any range, I don't consider this to be a major issue.
In most cases where a scope is purposely canted in the mount, it is done to compensate for the shooter's tendency to cant the rifle (this is often a stock fitting issue but one can address one or both to compensate). Ultimately consistency in hold and/or set-up will produce good results. If one feels a spirit level set-up is the answer for him, he should have one. GD

It is very similar to the bore sighter you have, this one is Bushnell and well made from decades ago before China. The bore sight is not rotated on it's axis in line with the bore, it is off center and actually tipped right of TDC in relation to the bore of the rifle.

I had pondered your idea myself and continued with a linear concept of aligning 2 separate grids of the scope and bore sight, but after playing around with it, you can see that alignment can happen with with the bore sight off center...

False

Yep, absolutely false. The center of the reticle has to be directly above the middle of the bore--which is how David Tubbs sets up his rifles. The reticle is canted in relation to the action, but the mounts put the center of the reticle directly above the bore.

If the center of the reticle isn't directly above the center of the bore, then the shots will land to the side of the aiming point, in the direction the reticle is off-center.

But if there is nothing in line in relation to the scope/bore you can still have the scope lined in one a single point that the rifle will shoot, but it will only be one point at one distance...

Well, yeah.

Same here. It works as advertised, and Hi-Vel himself is a great guy.

This is what always gets me with Talley screw and lever detachable rings, they aren't centered over the bore. For the life of me, no one will tell me why. I've called, written, sent pictures, etc. They'll admit they're not centered, but can't say why...

It's a bit of a brain teaser for sure. At the end of the day, I'm with Jordan; if it is very close to level on the rifle, and passes a tall target test, then it's GTG.

I would add that all of this is so much sturm und drang unless you are using a level mounted to the scope when shooting. And THAT level needs to be calibrated against "true plumb".... that's more important than if the scope is very slightly canted in the rings. A very slight cant (defined as the vertical crosshairs not bisecting the centerline of the bore), manifests only as a tiny offset. What matters is that it's pretty dang close to bisecting, and that the scope tracks plumb to the reticle, and that the level mounted to the scope is carefully aligned using a true plumb, and the shooter observers that level.

.... Or so it seems to me. Bit of a multi-variable equation and then there's the fact that rifles tend to lack flat surfaces to use as a reference.