Scope rotation/indexing

B

bluechip

Guest
I've had it!!! Every time I put a scope on a gun and spend a great deal of time rotating it until, when tightened, it is perfectly horizontal/vertical, one of *those* guys (certain friends) will look through it and say "your scope's crooked". I suppose it's like a picture hanging on the wall, everybody thinks it needs to be tipped a bit "their way". Is there a way to be certain that the scope is PERFECT and I can end these stupid 'opinions' and tell people "no, your eyes are crooked, the scope has been aligned perfectly"? I realise that it is probably not critical to accuracy to have the scope rotated within an arc second of true, but I really need to quiet my 'expert eye' friends. Help!
 
bluechip said:
I've had it!!! Every time I put a scope on a gun and spend a great deal of time rotating it until, when tightened, it is perfectly horizontal/vertical, one of *those* guys (certain friends) will look through it and say "your scope's crooked".
Click to expand...

Adjusting gear to impress anybody except the user is a complete and utter waste of time. G. David Tubb cants his sights to account for the way he holds his rifle.

Everybody holds a rifle differently. Unless you want to put your rifle in a return to battery rest, with a level on the rest and on the rifle and on the target to ensure that all of it is level and plumb, then you cannot avoid such comments from the dummies. Well, there's one way. Don't let those dummies cozy up to your gear.
 
scope leveling

bluechip: I know what you mean. One guy looked thru one of my newly mounted scopes & declared " Your crosshairs are canted 3 degrees". Of course, while he made this declaration, his girlfriend was standing nearby, and I wrote it off as him trying to impress her. The scope crosshairs were perfectly level. When mounting a scope at home I'll use a bubble level on the receiver, mount the scope loosely, bubble level on top of the elevation turret. That will get it close, sometimes, right on. Next trip to the range I'll take a carpenters level with me and check the level of the target frame, almost always level. The paper target will be stapled with the level on the top edge of the target, getting it level also. Back at the bench, it's real easy to verify level. Will have a set of torx wrench's with me to make minor adjustments, if needed.
 
Any chance they're just razzin' ya because they know they can get your goat? If not, next time ask them (Politely) how they mount and level a scope. Maybe they do know what the're talking about, maybe they don't.

I'm certainly no expert, but what I do is put my rifle in a rest and level it horizontally and vertically using a small bubble level placed on a/the base (Depends if one or two piece base) and clamp it (Rifle) down. I then put the scope in the rings and level the scope by placing the bubble level on the top turret and tightening down the screws, adjusting (Rotating) the scope if/as needed whilst tightening. Certainly there's some margin for error in that method, for example, how do I know the base(s) are on straight and level? I don't, but how else does one level a rifle? So without chasing my tail I go with what I got.

Some guys do something similar using a plumb bob. Level your rifle, set your scope, put a plumb bob out 25 - 50 yards and keep crosshair aligned with plumb bob whilst leveling. Sounds good, but I could only do that at the range as I have no other place to set a 'bob out 25 or 50 yards. And too, the West Texas wind would be swinging the 'bob like a metronome. :D I suppose I could put the 'bob in a bucket of water to try and keep it still. Take a couple gallon jugs of water, a bucket, hang the 'bob off my target stand, pour water in bucket, place 'bob in bucket. My try that some time. Hope that helps. Luck to ya.

Cheers,

Mark
 
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Mark,

There are a couple of things that you can do to give yourself confidence that your scope is set right:

(1) Install it initially with a good collimator. Because the collimator pivots on the centre of the bore & the scope in the mounts, the only time that the grid on the collimator & scope crosshairs can align is when both are adjusted so that they are square over the barrel. Any other alignment of either & the grid & crosshairs will be at an angle to each other.

Just make sure that you adjust the parallax on your scope (why do dorks like Leupold now call it focus?).

(2) Clamp your rifle up level & hang a plumb line some way off, enough so that you can get a good clean parallex adjustment. Your scope vertical crosshair should be parallel to the plumb line, if you've carried out the previous step OK. Then, making sure that the rifle isn't disturbed, with the vertical crosshair aligned with the plumb line, run the elevation up & down. It should coincide with the plumb line thruout its full travel.

If it runs off, then your alignment isn't correct or, if it's a Leupold, you have one with crosshairs out of whack.

John
 
John- Thanx mate. Interesting that collimator. I've seen them mentioned before but never gave it much thought. Have you got a recommendation for one? Thanx.

Well, there ya go bluechip.

Cheers,

Mark
 
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I use one of these http://www.microlevel.biz/vertical_retical_instrument.html
The problem with the illustrations is that they don't make it clear that there is a level built into the back of the tool.
If for a less critical application I set up in a rifle vise, and tilt the vise and rifle till I have the bubble in the middle, and one of the inverted Vs touching the scope and the other the barrel. Then you have the option of using a plumb line to set the vertical cross hair rotation, using a small level on the vertical turret or cap, or, after doing either of the above, taking it to the range and verifying that the cross hair intersection moves up a vertical line as the scope is adjusted up from its nearest range zero. Not that it happens very often, but if someone makes the mistake of telling me that a scope that I set up is crooked, I look him in the eye and tell he is wrong, and that I would be glad to show him how it was done when we have the time. Most guys set them by eye, and given that most shoulder with a cant, straight will almost always look crooked to them. On the other hand, if they hit what they are aiming at....
 
Well, I ain't got no "collimator" thingy, but I can suggest a poor man's device that'll get you vertical and horizontal all at the same time. Set up a frame out about fifty yards and hang a plumb bob on it. Choose a calm day. This method don't like wind. Level your rifle (I have a small torpedo level modified to fit across my barrel and it rests on the flats on the top of the fore end) and set the vertical cross hair of your scope on the plumb line. Tighten 'er up. Now this ain't gonna give you that knife edge accuracy you might find in some digital electronic device but you can't hold perfectly vertical anyway so don't fret about that. ;)
 
Scope alignment

I've had the same thing happen; someone tell me my scope wasn't level and he whipped out his little levels and sure enough it wasn't.... but neither were his levels :) I've mounted a fair number of scopes and re-set and bore sighted a fair number at the range that were installed by retail outlets and some have been off as much as maybe 15 degrees.

If you shoot long range you'll see your group shift to one side if the scope isn't level, same as if you cant your rifle with a level scope. You'll hardly notice that if you are only shooting at the range you are zeroed at. It would be handy to have a center mark on the top of the scope tube and a degree scale on the back scope ring so you have gage your adjustment. nhk
 
Ho'kay....... another opinion :)

First you must establish a relationship between your bore and your scope...... guys saying "GDavid Tubb shoots with his gun canted" neglect to mention that The Tubbman KNOWS where his bore is and that it may cause his shots to print 1/4min off-center... and he allows for it. His SCOPE is most definitely not canted to his trajectory.

Mere mortals must be more pragmatic IMO.

You must KNOW your sight is directly over your bore if you want to "sight in" on your crosshair, and IF your bore is truly under your vertical crosshair you must then establish whether the rifle itself is level.

This can be hard.

One way is to remove the front action screw and hang a hunk of 1/4X28 allthread down and plumb it. You figure out how to do this...... two tables maybe? Another is to have a flat on the action you can level to. Some will apply a level to the flats of the stock or to the scope bases....... Going off the flats on the stock may be OK although I've seen a whole lot of unequal ht stock rails. Something as seemingly simple as leveling a 700 action can get all sideways once you start trying to find a level point. The front base is often on a different plane than the rear... the action may be bedded canted into a twisted and crooked stock.....

So you get it close.

Now, with the rifle locked level you can level the optic. I'm with those who use an external source of level...... Doorframe, plumb line, neighbors corner board, whatever is PLUMB in the neighborhood.

I don't trust that the reticle hanger is level to the caps. I don't even trust that the hanger is level to the adjustment knobs under the caps...I trust nothing in or on the scope except the actual crosshairs and I don't trust THEM for tracking! With everything locked down you must then run the crosshair intersection up and down the plumb line to see does tracking coincide with the plumb reticle..... MANY do not, it's entirely common to see improperly installed hangers.

Only if your TRACK is plumb and you have a level on the rifle, can you actually dial in long range shots. Anybody who tries to simplify this process will be completely lost in a competition requiring that you actually hit things at mixed yardages.

opinionsby





al
 
El Paso Mark said:
John- Thanx mate. Interesting that collimator. I've seen them mentioned before but never gave it much thought. Have you got a recommendation for one?
Click to expand...
Mark,

I can't help you there. I've had mine maybe 40 years & over time, I've become comfortable that the grid on it was built accurately, based on how the shots hit out to 1200 yards when I true up a scope. The brand on it says Tasco, but it's boxed up a lot like others you see advertised branded Bushnell, BSA & Nikko, so who know's what the current crop is like.

Further to what al said, it helps that my actions have a flat tops so I can index the rig right first up with a bubble.

John
 
Being the simple minded git I am I try to line up the vertical "hair" with the center of the cocking piece or rear of the bolt by eyeball. That's plenty good enough for me and I've never had anyone complain. Mostly nobody looks through my scopes except me though, so....

If I do something for myself and someone else doesn't like it that's too bad, don't look at it then. :eek: :D
 
Aligning vertical

alinwa said:
Ho'kay....... another opinion :)
You must KNOW your sight is directly over your bore if you want to "sight in" on your crosshair, and IF your bore is truly under your vertical crosshair you must then establish whether the rifle itself is level.

This can be hard.

One way is to remove the front action screw and hang a hunk of 1/4X28 allthread down and plumb it. You figure out how to do this...... two tables maybe? Another is to have a flat on the action you can level to. Some will apply a level to the flats of the stock or to the scope bases....... Going off the flats on the stock may be OK although I've seen a whole lot of unequal ht stock rails. Something as seemingly simple as leveling a 700 action can get all sideways once you start trying to find a level point. The front base is often on a different plane than the rear... the action may be bedded canted into a twisted and crooked stock.....

So you get it close.

Now, with the rifle locked level you can level the optic. I'm with those who use an external source of level...... Doorframe, plumb line, neighbors corner board, whatever is PLUMB in the neighborhood.

I don't trust that the reticle hanger is level to the caps. I don't even trust that the hanger is level to the adjustment knobs under the caps...I trust nothing in or on the scope except the actual crosshairs and I don't trust THEM for tracking! With everything locked down you must then run the crosshair intersection up and down the plumb line to see does tracking coincide with the plumb reticle..... MANY do not, it's entirely common to see improperly installed hangers.

Only if your TRACK is plumb and you have a level on the rifle, can you actually dial in long range shots. Anybody who tries to simplify this process will be completely lost in a competition requiring that you actually hit things at mixed yardages.
al
Click to expand...

True enough. I didn't mention that I always start with the scope optically centered for vertical and use a windage base to align vertically with a bore-sighter in the muzzle and the top of the one piece scope base to level horizontally. The guy that said my scope wasn't level was going off the stock and he was right, for the stock. I checked his little magnetic levels against my 2 foot carpenters level and they were off.

I got a set of the levels that has one for the action rails and the other for the scope cap and found the vials are just pressed into the plastic (loose) and molded plastic tends to warp when cooling and the magnet material is glued on. I had to sand them down on one end to get them level and recheck them before and after I use them. nhk
 
Thanks to all for your input/support. Maybe from now on I'll start a policy that states, "I'm sorry, but I don't allow anyone to look through my scopes".
 
Let 'em look

bluechip said:
Thanks to all for your input/support. Maybe from now on I'll start a policy that states, "I'm sorry, but I don't allow anyone to look through my scopes".
Click to expand...

Just smile at 'em and proceed to knock another varmint off it's mound. nhk
 
I guess what got me all worked up was the fact that I spent quite a bit of time aligning the new Nikon monarch ED 8-32x scope and sighted it in at 80 yds (222 Rem 700) and put three out of four in not only the same hole, but exactly in the center of the bullseye. The scope was loaded with nice features like side parallax knob, an adj. for use without eyeglasses (+ or - 2 diopter strengths) and is beautificly clear, but instead of commenting on any of the plus features, all I got was a "your scope is crooked". Thanks for letting me vent, I can see most of you guys here are *been there, done that*.
 
bluechip said:
............but instead of commenting on any of the plus features, all I got was a "your scope is crooked". Thanks for letting me vent,
.......
Click to expand...

What's wrong with "thank you for noticing the crooked scope. I'll fix it, and it'll shoot better...."

??

Sounds like something I would have said though.... I just don't know how to "say the right thing" for every personality type. I'm more about trying to share a constructive opinion.

ohh well, it takes all types

al
 
My hawkeye borescope has shown me many barrels with marks on the top
of the lands where a colimator was used. I no longer rely on one for
leveling.
 
A collimator is useless on a high fixed power scope. Need to get down to about 6 power to see the reticule clearly.

Here is an easy fix for a BR rifle with flat 3" foreend. I use a padded cleaning station. Lay the rifle loosely in it. Find a small rectangular level and a popsicle stick. Glue one side of the small level to the stick, and lay it on the underside of the stock. Hold it in place and tilt the rifle until it is level. Take another small flat level and place it on the elevation cap. Twist scope until the upper level bubble matches that of the lower level, and you should be right on.

If yours is not a flat BR stock, take a small square with level in it and match up the holes vertically on the recoil pad. When the bubble level centers, turn the scope (with the small level laid on the scope elevation turret) until it also centers.

Verify this at the range with a target containing one inch squares, levelled at the top of the paper, and viewed from 50 yards.
 
Tell em the crosshairs are canted to compensate for gyroscopic bullet drill, and that they must have excellent vision to have seen this, very few people would have noticed.
Next thing you know they'll go home and cant their scope as well, that being the new thing, soon everyone will be doing it and articles on the proper method of canting your crosshairs will begin to appear in the gunrags with many pet theories on the exact angle.
 
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