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RoyB
01-10-2008, 08:37 AM
Aligning scope to bore parallel?????

How are you folks lining up your scopes to be absolutely certain it is parallel with the bore. I'm using windage adjustable bases. But if I get it windage adjusted at 100 yds, it could be way off left or right at 500 if the scope isn't perfectly parallel to the bore...

Brownells used to sell a 30" x 1" rod just for this, but there was no way to reference it to the bore.

Any ideas?

Spott3r
01-10-2008, 08:43 AM
Pick the distance at which you would like to shoot.

Then I'm thinking use two lasers to line it up.
I have never tried this but it would line you up with your target pretty good.

Just a thought.

John
:D:D:D

RoyB
01-10-2008, 08:44 AM
Anyone use one of these

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

nstructions for the Vertical Reticle Instrument



Important Safety
Information

Safe handling and use of firearms depends on you.

Always follow the manufacturers safety instructions provided with your firearm. If you do not have this information contact the manufacturer of the firearm and request it.

Always follow established firearm safety rules and practices.

Firearms retailers and shooting ranges can also provide you with or direct you towards information and training about firearm safety and instruction.
The Vertical Reticle Instrument

will help you to position your scope's reticle during the scope mounting procedure so that the vertical crosshair will be aligned precisely with the center of the bore. This alignment is desirable because only when it exists does the vertical crosshair represent the true rise and fall path (trajectory) of your bullet. When this alignment is in error the path of the bullet moves from one side of the crosshair to the other side at the distance it was sighted in.

The Vertical Reticle instrument is simple to use and extremely accurate. It is a precisely machined tool that should be handled and stored with care. Read these instructions carefully and follow them closely when using the Vertical Reticle instrument.

Instructions for use of the
Vertical Reticle™ instrument




Always be certain the firearm or gun is fully unloaded and the action is open before using the Vertical Reticle instrument. Never under any circumstances load or shoot a firearm with a Vertical Reticle instrument attached to it.





illustration 1
STEP 1
Choose a vertical reference line which may be easily and clearly viewed through your scope. There are a number of possibilities to choose from, a few suggestions are provided below:

Good: The edge of a door or window jamb or vertical lines in wood paneling.

Better: A dark line scribed onto an inside or outside wall using an accurate carpenters level as a guide.

Best: A string under tension from a freely suspended heavy weight.

Avoid: Telephone poles, flag poles, fence posts, etc. are poor choices.

Note: Some scopes will not bring nearby objects into focus which may make it difficult to work indoors. Looking through a window to a vertical reference line outside may be an option.











STEP 2

Stop!!! Before proceeding be sure the firearm is unloaded and the action is open!!!


Cradle the gun securely in sandbags or a gun rest so that the barrel is held in a horizontal (level) position and the vertical reference line chosen in step 1 can be viewed clearly through the scope such as shown in
illustration #1.

Loosen the screws on the scope rings just enough so that the scope may be rotated within the rings with a gentle effort.

Loosen the thumb screw slightly so that the barrel V-block and the scope V-block position setting can be adjusted. Place the Vertical Reticle instrument onto the scope and barrel of the firearm as shown in illustration #2.






illustration 2
Important - Note that the scope and the barrel must each contact both surfaces of each V-block, four contact points in all, during all measurements and observations.

A small rubber band may be looped over the objective end of the scope and the exposed threaded end of the thumb screw to help hold the instrument in place but be certain the four contact points are maintained.

STEP 3
Now slowly tilt the firearm slightly from side to side until the bubble is centered exactly between the calibration marks of the level vial. Then view the vertical reference line you have chosen through the scope. If the vertical crosshair of the reticle is not perfectly parallel with the vertical reference line the scope body must be rotated slightly and these steps repeated again. Repeat as necessary until perfectly parallel lines are achieved as shown in illustration #3.

Before tightening the screws of the scope rings double check your work:



illustration 3
1. The vertical reticle instrument has four points of contact.
2. The bubble is centered exactly between the calibration marks.
3. The vertical crosshair is exactly parallel to the vertical reference line.

Tighten the screws on the scope rings gradually and evenly to prevent any minute rotation of the scope.

After the screws on the scope rings have been fully tightened make a final check of your work:

1. The vertical reticle instrument has four points of contact.
2. The bubble is centered exactly between the calibration marks.
3. The vertical crosshair is exactly parallel to the vertical reference line.

The procedure is now complete and you have successfully aligned the vertical crosshair of your scope accurately with the center of your bore.

Diagnostics and Troubleshooting using the Vertical Reticle instrument



The Vertical Reticle instrument will perform an accurate reticle-bore alignment regardless of any misalignment of the scope body itself with the centerline of the barrel. When a significant misalignment does exist between the scope and firearm, the Vertical Reticle instrument can expose this problem, therefore enabling you to take corrective measures.

If after the completion of the third part of STEP 3 of the reticle alignment procedure it is noticed that the firearm itself appears or tests out to be leaning slightly to the left or right (see illustration #4) when the other conditions are met, this is an indication that: l ) Either the scope body itself is not mounted at top-dead-center above the action and/or 2) The alignment of the scope body is skewed with the axis of the barrel.

The second condition is easy to remedy if the scope mounting system includes windage adjustments. Otherwise both conditions can be difficult to correct and may not be worth the trouble. A "cosmetic" and serviceable reticle alignment can be performed by placing the Vertical Reticle instrument on the end of the stock as shown in illustration #4 and performing the tasks of STEP 3 again.

JerrySharrett
01-10-2008, 09:08 AM
Aligning scope to bore parallel?????


Brownells used to sell a 30" x 1" rod just for this, but there was no way to reference it to the bore.

Any ideas?
If you are using Leupold or Millet type rings, the adjustable kind, center the windage adjustment on your scope. Then, at the range, using a stable bag setup, boresight on something a good distance away, at least 100 yards.

Then adjust the rings so the cross hair is as close as you can get it. That should be close enough for hand grenades and horse shoes, and scopes.

Bill M
01-10-2008, 09:09 AM
I don't care for windage bases and don't use them, but if I wanted to make sure the tube was true to the bore I would center the erector assembly in the scope tube, then use the windage mount screws to set my initial zero/bore sight:

http://www.usoptics.com/index.php?page=instructions

Cheers,

Bill

Edited to add: What Jerry said - he beat me....

RoyB
01-10-2008, 09:17 AM
But all of the above methods only assure the scope is aligned at one particular spot in space. If you did the above at 100 yds, that is the only spot in the universe that you can be sure the reticle is aligned with the bore. If you now sight in on something 500 yds away, unless the scope is perfectly parallel with the bore of the barrel, your shot will go either right or left. And this is compounded even more if you "click" up and down at different ranges, because now a very slight cant of the verticle crosshair is greatly magnified as you move the crosshairs up and down.

The method of hanging a weighted string some distance down range, and then bore sighting onto that string (or using a bore sighted laser) and then lining up the crosshairs on the string still only accomplishes a "one point in space" accuracy.

Someone must have thought of a better way to accomplish this task.......You would think the 1000 yd boys would have this figured out......

WhelenMan
01-10-2008, 09:55 AM
If you're using the Burris Signature rings just put a little degree of offset in the inserts after centering the adjustments on the scope. I wound up with a 20 moa insert in my rear ring and a 5 moa insert in my front ring. I wound up with about a 30 degree rotation on the 5 moa insert to get my scope aligned. Do this while using a bore scope. Several trial tightenings of the rings may be necessary to get to the right point.

Gunner223
01-10-2008, 10:24 AM
A Sweeney columnator works well for me. I have been using one for many years.

Don

Vibe
01-10-2008, 11:02 AM
You repeated the question at another site, I'll repeat my answer here. :D

Which do you want? You are describing two separate things. related yes, but separate.

If you set your scope up and get the crosshairs optically centered, and use the scope mount windage adjustments to get dead center left/right at 2 extended ranges, then you then know that the scope tube is parallel to the bore. If it is centered at one range and off at the other then you know that the scope is not mounted directly above the bore. You can correct some of this through trial and error by repeated shooting at both ranges and alternating the adjustments between the front and rear mount adjustments. If you are dead on at 100 (and got there by adjusting the front mount), but are hitting to the right at 150 or 200 (and wind and rifle cant is not the issue). Adjust the rear mount to get to L/R zero @200. This will put you off at 100 again, but by an ever decreasing amount.

At no time during this exercise should you even think about touching the scope windage/elevation knobs.
The scope should remain optically centered in it's tube during the whole exercise.

Only then can you start to worry about whether or not your reticles are square with the world.

Bill Myers
01-10-2008, 12:34 PM
TAke a peice of 1" stock & machine a hole into the exaxt center of it that will allow a small lazer to fit in it snug,This goes into the Rings & is put on target at say 50 yds or whatever.You know that the lazer is in the center.Now you need one of the lazers that fits into the bore of the rifle.You can now adjust what ever to align the 2 dots,you can not reley on a scope to be centered perfect,If you need one for 30mm,Make a second one to fit the 30mm rings. BILL

RoyB
01-10-2008, 02:35 PM
Bill,

Your "laser" device will still only give me "one point in space".......no different than simply bore sighting and then aligning scope to hit where the bore is pointing. But again, only at that specific range..........

Nope...There has got to be a better method..........

RoyB
01-10-2008, 02:37 PM
Using two targets at two different ranges,(50 and 200 might work best) is the best idea. But then you have atmospheric conditions to deal with (wind).....

There has to be a way to use an indicator rod down the bore and a 1" piece of drill rod in the scope rings and some way to align between them.........

lcw
01-10-2008, 02:54 PM
how could using drill rod in the gun and rings get you any different result than the method proposed by a few guys with the lasers????

My second question would be....why so hung up on parallel, almost all the guys use one or more of the methods described in these replies to bore sight and align their scopes.

Just curious.
Linc

Dennis D.
01-10-2008, 04:51 PM
One thing you might consider, unless the bore is exactly in line with the receiver point of impact wil change as distance changes as there will be an angle between the barrel and receiver where the scope is mounted, the gun will always be shooting sidways and all you can do is adjust point of impact as the range changes.

Dennis

RoyB
01-10-2008, 06:37 PM
The laser would work if you did the alignment in a smoke filled room, where you could see the laser beam as a "line of light" rather than a dot in a predetermined target distance. But you would still need some method of correlating the beam of light to the bar resting in the scope rings..........

The bore and the center line of the scope needs to be perfectly aligned otherwise as the distance changes, the convergence of the bore and the center of the scope will change left or right...........

All of the methods listed thus far do not take into account this issue......

Bill Myers
01-10-2008, 07:43 PM
Roy,I think that now understand what you are after,What you need to do ,is use 4 lazers,One in each end of the 1" bar & one in each end of the barrel,You will have a set of lazer dots in each direction & thus ,you can see how much misalignment you have between the barrel & the action mounted rings.The Barrel will need to be straight or the lazers will not show a truebore line.You could set it up in a room & use the wall in opposite directions for the course alignment & set them farter apart for a fine tune.I do not know where you can get the lazer for the chamber end,you might end making a adapter yourself. BILL

Jackson~in~GA
01-10-2008, 09:14 PM
I realize I am not a benchrest guru, but as long as the crosshair is centered what difference will it make if the scope is not one hundred percent inlined. Perhaps I am missing something, but I don't see how a slight misalignment can change point of impact (left to right) as long as the cross hair is zeroed?

RoyB
01-11-2008, 05:43 AM
Bill,

Excellent idea, and that would work! Both "sets" of lasers would need to hit two vertical lines in front and rear of the rifle, drawn on opposing walls............Perfect!

Thanks

RoyB
01-11-2008, 05:57 AM
Jackson...............I hope this "CAD" (Crayon Aided Drawing) helps explain what I'm talking about.

I understand that the misalignment will be very little, but it would be nice if when you click "up", the bullet simply went up and not left to right some amount......

http://images33.fotki.com/v1070/photos/3/36012/69369/misalignment2-vi.jpg

Dusty Stevens
01-11-2008, 05:59 AM
I have never had this issue in benchrest:confused:

Vibe
01-11-2008, 11:36 AM
I have never had this issue in benchrest:confused:
Unless you shoot multiple ranges (distances, not locations :D I'm guessing you shoot other places than just Benton :D) with the same rifle, you won't. Many rail guns have the scope mounted off to the side by a noticeable distance.
It can come into play in silhouette shooting though, and varminting where the distances vary from shot to shot.

As for laser alignment, use a boresight laser instead of shooting and still use the practice I described - aiming at vertical lines at two separate ranges. Either way , once you have the mounts in alignment, you still have to mount the scope with the adjustment travel in line with this alignment. I guess it would give you the chance to be sure that the reticle is in alignment with the adjustment travel. :D

The reticle is mounted separate of the erector tube in most scopes.

JeffL
01-11-2008, 11:45 AM
Would this work? Insert a laser in the bore. Hang a weighted string, so it is perfectly vertical, about 30 to 50 feet away. Aim the laser so it hits the string and then projects on another more distant target, like 50-100 yards. If the center of the scope reticule hits the string and the distant laser point, it will be alligned.

Vibe
01-11-2008, 11:52 AM
Would this work? Insert a laser in the bore. Hang a weighted string, so it is perfectly vertical, about 30 to 50 feet away. Aim the laser so it hits the string and then projects on another more distant target, like 50-100 yards. If the center of the scope reticule hits the string and the distant laser point, it will be alligned.
That should get you there. Thanks for the simplification. Provided that the scope was optically centered to begin with. You could then run the elevation adjustment up/down to verify that the reticle is indeed inline with the adjuster.

Gene Beggs
01-11-2008, 12:26 PM
I will have to study this for a while, but I think it may explain something I have been observing for years. Very interesting indeed. The pieces of the puzzle continue to fall in place. Keep the feedback coming.

Gene Beggs

JeffL
01-11-2008, 12:38 PM
Could one also turn the scope 90 deg and run the vertical up and down to check it?

Vibe
01-11-2008, 01:05 PM
Could one also turn the scope 90 deg and run the vertical up and down to check it?
People with steep ejecting rifles have been running scopes mounted at 90° for years. You just have to remember that the turret marked "U/D" is now windage, and the one marked L/R is now elevation. And in some scopes the range of adjustment may vary between the two. But just to check linearity? Sure why not. (You have my permission to do so. :D Like you needed it :D)
You would also probably need to redo the optical centering between tests.

JeffL
01-11-2008, 01:14 PM
I will have to study this for a while, but I think it may explain something I have been observing for years. Very interesting indeed. The pieces of the puzzle continue to fall in place. Keep the feedback coming.

Gene Beggs

Gene
I"m curious what it is that you have been observing.

JerrySharrett
01-11-2008, 01:23 PM
Could one also turn the scope 90 deg and run the vertical up and down to check it?
I have seen Boyer rotate a scope in the rings to see if the reticle is in the center. What does that help??? Dunno!! This was on a Farley where the scope bases bolt on.

Viewing from the vertical plane, the only scope mountings that would not be parallel to the bore probably would be on some of the old actions (Mauser 98's etc) where the scope base screw holes were drilled without a jig or milling machine setup and were off center in different directions.

The right hand spin of a right hand twist barrel will take the bullet out of the vertical zero. I have a 6mm on a Panda, that at 600 yards, and the horizontal drift due to twist is about 2".

Now, gun cant is another story.

Dog's Elvis
01-11-2008, 02:17 PM
RoyB:
I use the Verticle Reticle Instrument you mention and believe it to be a "must have" for accurate hunting rifles (the kind of sporter that may be employed at 400-plus yards) and long-range rifles shot at varying distances and from rests other than front rests and bags used in competition -- but I should add that I almost always employ some type of level (indicating side-to side cant) mounted on the scope or mounting system. It's certainly not a cure-all, and its usefulness, for my purposes, is minimal until extended ranges are involved, and then one's wind reading and adjusting abilities, as usual, are the primary issue.
Well, maybe "must have" is a bit too strong, and I've been wrong before. And there's certainly other noise that is heard, such the bullet spin Mr. Sharrret refers to, that may drown out the noise I'm trying to muzzle. And maybe all the gizmo does on a factory gun is help get the reticle reasonably "vertical" to the bore (right angles being less common in some reticles than one would hope). I wll say that Remington doesn't always drill their mount holes with sufficient precision.
For known-and-constant-range competition rifles shot off very stable (and therefore repeatable) rests it may not be a big issue -- I dunno. But I have that gizmo, and I use it, and it adds to my confidence in my long-range shooting and hunting abilities.

RoyB
01-11-2008, 06:20 PM
Thanks Folks! Great conversation.............

Most, if not all Remington actions I've ever measured have the scope mounting holes off center to the bore of the action.

Savage actions tend to be spot on. I've also had all kinds of off center problems with Ruger rifles...

Currently, I use nothing but Millett Angle Locs, Nikon or SK Kontour rings and mounts because they all offer both front AND rear windage adjustment.....

http://images22.fotki.com/v836/photos/3/36012/753161/Vac8-vi.jpg

http://images108.fotki.com/v607/photos/3/36012/69369/P1010007-vi.jpg

http://images22.fotki.com/v837/photos/3/36012/820948/20Tac5-vi.jpg

http://images25.fotki.com/v904/photos/3/36012/69370/P1010004-vi.jpg

http://images25.fotki.com/v899/photos/3/36012/69370/P1010007-vi.jpg

John Kielly
01-11-2008, 06:58 PM
But does it prove anything in the end?

I have a rifle I shoot 200SMKs & 210 SMKs & Bergers thru & the 210s print 3 inches to the right of of the 200s at 100 yards, but once zeroed at theat distance for either, my 1200 yard zeros are consistent with the short range strike (as wel as you can judge in such circumstances), though I'm certain enough to make alterations & expect a centre hit when the flags cross the pole.

Dusty Stevens
01-12-2008, 05:00 AM
hey Vibe- where you shootin in benton? I usually travel to shoot matches.

LASER
01-12-2008, 08:48 AM
A Sweeney columnator works well for me. I have been using one for many years.

Don

is what I spend my days striving for. I build particle analyzers that utilize three lasers. This focus parameter is a must for our product to measure accurately. This also explains my log on. Could you describe your set up? I could probably implement it at work. One can sure tell it's winter, can he not? Thanks

LASER

Gene Beggs
01-12-2008, 12:04 PM
Gene
I"m curious what it is that you have been observing.

Jeff, after studying about it, I do not believe this is related to what I was thinking about.

When I first got involved in this obsession called benchrest back in 1988, my first rifle exhibited a trait that I have yet to understand. The rifle was a Hall sporter in a Hall stock built by James Messer with a Hart 13 twist LV barrel and a Leu 36 scope. At the time, I did not realize just how good it was, but have since realaized, I had a real jewel!

My mentors, Charles Huckeba and Cecil Tucker advised me to put that barrel away and save it for the big matches, but, ignoring their sage advice, I foolishly burned it out in about a year. Here's what it would do.

Let's say you have four shots in a dot, when the condition goes away and will not come back. Time is running out and you know you are going to have to fire a sighter and hold off. With that rifle, you could go to the sighter, hold the same point of aim used with the preceeding four shots and fire the shot, then place the dot back on the point of aim and carefully, without disturbing the rifle in the bags, move the dot over to the bullet hole with the scope turrets. You could then go back to the record, hold on the GROUP and that shot would go right into the hole every time! It was the damndest thing I ever saw; it would do it every time, and I have not had a rifle since that would. Oh, I have had several barrels that were very accurate; one that even earned a couple of HOF points for me, but I have never had a rifle/scope setup that would duplicate the behavior of that first rifle. It now belongs to a friend of mine, Street Rogers, a captain for America West airlines who lives near El Paso.

Some would say, "Well, you're just disturbing the rifle when you make your scope adjustment." but I don't think so; I have even tried it with a rail gun. Others may say, "Well,, you're not firing the two shots in the same condition; you're missing a change, and that's what's causing the shot to go astray."

For years, I have thought about this and have yet to understand it. I have also tried it in the tunnel and it will not work there either. It seems simple; you put the dot on the point of aim, fire the shot and tweak the crosshair over to the bullet hole. If the rifle is shooting, the next shot should strike precisely at the point of aim, but it rarely does. It seems that the scope adjustment always results in about twice the change in point of impact as I expect. Anyone got any ideas about this?

Gene Beggs

Vibe
01-12-2008, 01:27 PM
hey Vibe- where you shootin in benton? I usually travel to shoot matches.
The Benton Gun Club
http://www.bentongunclub.org/
I've shot in a couple of matched there - once upon a time. Always wanted to join, but life has seemed to have gotten in the way. :D One of these days....

JerrySharrett
01-13-2008, 08:21 AM
For years, I have thought about this and have yet to understand it. I have also tried it in the tunnel and it will not work there either. It seems simple; you put the dot on the point of aim, fire the shot and tweak the crosshair over to the bullet hole. If the rifle is shooting, the next shot should strike precisely at the point of aim, but it rarely does. It seems that the scope adjustment always results in about twice the change in point of impact as I expect. Anyone got any ideas about this?

Gene Beggs
Gene, one thing that may effect your exercise of clicking over, I think most times when we hold off, we hold too much. i.e. What looks like a bullet and a half change on the sighter, I think we end up holding 2-1/2 holes.

How many times have you heard someone say "I held xxxx and it went exactly where I held"? In the instance where you clicked over was an exact amount of where you held versus where the bullet actually went not what our mind pictures it.

Gene Beggs
01-13-2008, 04:11 PM
Jerry, what I have always done is the same thing we do when sighting in any scope sighted rifle. i.e., hold a precise point of aim (I center the dot in the mothball), fire the shot then place the rifle back on the point of aim as when you fired the sighter, which in this case would be center the dot in the mothball. If the bullet hole is say high and left, carefully move the dot with the turrets until it comes to rest directly over the bullet hole. All this without disturbing the rifle in the bags. This should, theoretically, bring the point of impact perfectly in line with point of aim. Like I said, in spite of my best efforts, I have been unable to duplicate what I experienced with that first Hall sporter.

Gene Beggs

Don
01-13-2008, 05:45 PM
Jerry, what I have always done is the same thing we do when sighting in any scope sighted rifle. i.e., hold a precise point of aim (I center the dot in the mothball), fire the shot then place the rifle back on the point of aim as when you fired the sighter, which in this case would be center the dot in the mothball. If the bullet hole is say high and left, carefully move the dot with the turrets until it comes to rest directly over the bullet hole. All this without disturbing the rifle in the bags. This should, theoretically, bring the point of impact perfectly in line with point of aim. Like I said, in spite of my best efforts, I have been unable to duplicate what I experienced with that first Hall sporter.

Gene Beggs

Hi Gene,

That tells me you are having a "sighter to record target" change that is occuring due to angular differences to the gun as it is positioned differently on the 2 different targets, which can make for oscillation differences or bag reaction differences.

Notice, that if you make these same target/scope adjustment changes during a practice target shooting session, with a practice target that has multiple bullseye aimpoints located horizontally within a couple of inches of each other..............the impact change will be non-existent or almost unnoticable with a scope adjustment change for new wind condition, at least it has for me.

Like you, Ive seen where some guns have a greater "sighter/record target" reaction than others and I have not been able to determine what the causation factor is for those guns that handle this change better...................Don

JerrySharrett
01-13-2008, 08:39 PM
I have been unable to duplicate what I experienced with that first Hall sporter.

Gene Beggs
Now Street has that Hall and he has a nice South Bend Heavy 10. He must be blessed!

I've noticed many times with rimfire BR that the POI changes greatly when moving from a centerfire group targets sighter target to the record target. And this is at 50 yards & 50 meters. Just the change of how the stock contacts the bags when moving up and down seems to cause this.

In shooting rimfire score, changing from one row to the next will many times invoke a POI change. Some of the rimfire score organizations like ARA have a sighter bull outside of each end of each row.

Dusty Stevens
01-14-2008, 12:02 AM
The Benton Gun Club
http://www.bentongunclub.org/
I've shot in a couple of matched there - once upon a time. Always wanted to join, but life has seemed to have gotten in the way. :D One of these days....


well, you ought to meet me down there sometime when you get a chance