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I am confused, not the boresight. I was asked to sight-in a Rem 742, which had been boresighted by the retailer of the scope. First shot at 100 yards kicked dirt up onto the target! Eighty-five clicks later, I am centered on the bull. I then put my own Bushnell Bore Sight into the bore and the cross-hairs are all the way to the bottom of the bore sight grid! Removed and replaced the bore sight (to be sure it was in the bbl correctly) and got same image.

Can anyone explain this to me? I plan to shoot it at 200 yards (as soon as the weather warms up a bit) to see if it is still on at that range. I am confused and baffled. [Confession: a frequent occurrence]
 

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Question

Assuming it has iron sights, does it shoot to point of aim with the irons or is that way off also?

If it shoots pretty close to your point of aim with the iron sights I would suspect something wrong with the rings, scope mounts, or scope. Do you have another known good scope you can substitute? If another known good scope is also way out of the ball park I'd be trying to verify that the rings and mounts were correct for the application and installed correctly.

Hope that helps a little.
 

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Also is the forearm on that rifle properly installed and secured? If it wasn't it could be causing undue pressure or stability issues for the barrel.
 

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Bore sight devices are designed to be used at 25 feet. If the scope is boresighted at anything other than that the scope crosshairs will not be centered properly. Seldom in a shop will there be a 25 feet area that can be used so the shop will bore sight at a much lessor distance. I, today, watched a clerk at Sports Academy bore sight a customer's rifle at almost 4 feet...eeeh...wrong. You may get away with 20 feet or even 30 feet but 4 feet; doubtful.

Additionally, a clerk or dealer cannot boresight YOUR scope properly even if he has the correct distance. I say this based on the eye relief of the dealer will not necessarily be the same as his customer. It is always best to save your money and bore sight the rifle/scope yourself because chances are you will need to redo the sigh-in yourself anyway.

The bore sight device will not put an accurate point for your scope, it is designed to get you 'in the ballpark'...fine tuning must be done at the range and at the distance you want to shoot.

After you bore sight it, start at 50 yards until your shots are in the black, then move to 100 yards and set your scope to poa/poi. Once you are in the black with an acceptable group at 100 yards you can adjust your scope for approximately 200 yards by raising the poi 1-1.5 above your poa. Of course the best is to shoot at 200 yards for the best poa/poi.
 

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Bore sight devices are designed to be used at 25 feet. If the scope is boresighted at anything other than that the scope crosshairs will not be centered properly. Seldom in a shop will there be a 25 feet area that can be used so the shop will bore sight at a much lessor distance. I, today, watched a clerk at Sports Academy bore sight a customer's rifle at almost 4 feet...eeeh...wrong. You may get away with 20 feet or even 30 feet but 4 feet; doubtful.

Additionally, a clerk or dealer cannot boresight YOUR scope properly even if he has the correct distance. I say this based on the eye relief of the dealer will not necessarily be the same as his customer. It is always best to save your money and bore sight the rifle/scope yourself because chances are you will need to redo the sigh-in yourself anyway.

The bore sight device will not put an accurate point for your scope, it is designed to get you 'in the ballpark'...fine tuning must be done at the range and at the distance you want to shoot.

After you bore sight it, start at 50 yards until your shots are in the black, then move to 100 yards and set your scope to poa/poi. Once you are in the black with an acceptable group at 100 yards you can adjust your scope for approximately 200 yards by raising the poi 1-1.5 above your poa. Of course the best is to shoot at 200 yards for the best poa/poi.
You're "right on target" oldjarhead. A gunshop employee was supposed to boresight my model 94 a couple of months ago and I watched him as he aimed at a spot around 4 ft away.(ha) He asked me how far I wanted it sighted in for and I said 100 yds.

So...when I went to a country field below a big hill and set up a target. First shot hit about 50 yards out so I reset the elevation screw. Next shot was around 75 yds out so I increased the elevation screw again. After two more shots I was finally hitting the 2 ft sq board where the 8" circle had been drawn. After hitting the board consistently a couple of more times I decided to leave it alone for the time being.

My point is that the gunshop salesman didn't use a proper setup for boresighting. It cost me because I had to fire several rounds to get it corrected to where I think it should have been from the beginning.
 

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Discussion Starter #6
Yup, lots of confusion...

The rifle is sighted in and groups about 2 MOA at 100 yards. The bore sight I use is a Bushnell with arbors, as did the scope vender. It is not a laser device. The aiming screen is attached to the muzzle.

With most centerfire rounds the bullet ascends up through the line of sight at about 23 yards. Hence, a laser on target at that range (yards) should be on target at about 100 yards. I agree and understand your comments. However, my device simply provides a screen with a grid for the scope to be adjusted. It is usually "on paper" with reasonable care. However, this rifle is "on" at 100 yards, but the bore sight device says it is way off. In fact, when zeroed by the bore sighter, the bullet impact is way off!
 

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Could the barrel be bent/crooked.?The bullet will gyro some.I can have one bullet hitting zero,and change weights og bullet and it will hit off to the side from where the different bullet hit.
 

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after listening to you it is probably safe to say there is something wrong with youur arbors or the"screen" and judging y how far off it has to be to be on the papper it may also be your scope mounts check the height of both from the reciever to the tube
 

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It's likely the height above the bore that is the problem. With an optical boresighter an extension may be needed if the scope is mounted high above the bore. The Bushnell is best suited for very low mounted scopes if it's the one I'm thinking of.
 

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When you are using a boresight at under 25 yds. you should sight above, a inch or so of your boresight`s spot.............A boresight is just to get you on the paper.
 

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I believe that Para Cassat has it. If you are using the muzzle device, I'll call it, it has to be affected by scope mount height. I have never used one, but I've watched them used a few times. But by simple reasoning, this has to be true. I would guess that you are using low pro scope mounts, and the grid is set up for peek throughs.
 

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i wonder if there arbors might have been bent a tiny bit. or drop once upon a time and got messed up. i had a BSA set that i accidently drop and it messed up to the point of being off by feet. i bought a new one same style and pused it and it was only off by a inch or two
 

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Eighty five clicks? How far from being centered are the crosshairs? With that amount of clicks to get to 100 yds. you might run out before getting to 200.
I'd be casting a jaundiced eye at the bases and rings rather than the bore sighter.
 

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It has been said above...bore sighters are not made to be used at long distances...Use it at 25 yards, then fire at 25 yards and just center the hits.
It will be on paper at 100 irregardless of scope height which has a MINOR effect on the sighter. Sadly the mount choices have used up so much of your scope elevation, but if you still 40 clicks left, you are still good to 400 yards. If not you may have to shim.
 

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one easy way to check is on another rifle that you know is sighted in. Many factors effect a bore sighting device. I have multiple scoped rifles and no 2 are the same on the bore sighter. I use graph paper in a folder to record the propper settings for each rifle after the final sight in so if needed I can return the scope to the propper setting. Just a suggestion
The best way to bore sight a bolt or single shot is to actually look down the bore and align it with the target with the rifle in a stable rest. Once the rifle is aligned the adjust the scope and it should get you on the papaer for finer adjustments.
 

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I use the same type of bore sighter you do, and it has never been 100% on the dot to me. I am usually 1 line down and a couple to the right of where the bore sighter says I should be when I am hitting perfectly at 100 yards. I think these things are just for a very rough guesstimate. Enough to get you on paper is all.
 

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one easy way to check is on another rifle that you know is sighted in. Many factors effect a bore sighting device. I have multiple scoped rifles and no 2 are the same on the bore sighter. I use graph paper in a folder to record the propper settings for each rifle after the final sight in so if needed I can return the scope to the propper setting. Just a suggestion
The best way to bore sight a bolt or single shot is to actually look down the bore and align it with the target with the rifle in a stable rest. Once the rifle is aligned the adjust the scope and it should get you on the papaer for finer adjustments.
This is my preferred method as well. I have a pretty cheesy Tasco boresighter that does work, but it's never been very accurate. The best use I've found for it is to check the scope against it after it's been properly sighted in and record the results for future reference. I didn't do this on my .270 and it recently cost me over $50 to get it re-sighted (two trips to the range during my lunch hour, plus gas, targets, staples, ammo, etc.).
 

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I just center the reticle , mount the scope , and shoot at 25 yards . 99% of the time , it's on paper . I fire a three shot group , then move POI to bullseye . then go to 100 yards . Usually it'll be 2 or 3 in. high at 100 and will need a little windage fine tuning . I've never understood the mentality of going to the range to fire as few shots as possible ! When I go to the range I try to fire as many shots as possible , especially if it's a new rifle or scope . I like to get as familiar and comfortable with my guns , as I can , doubley so if it's a rig I'm going to hunt with ! If you have those stupid see through mounts , a boresighter doesn't work at all , the scope is way too high above the bore , you use up all your elevation adjustment just finding the grid in the boresighter !
 

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how high above the cenerline is the scope?
how high above the centerline is the boresighter?
yeah 2"s and 1/2" is a bit different.
 
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