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Discussion Starter · #21 ·
No, it's not lupus!

Hey your calipers out and masure your bases and rings, then do the math. How much actual can't are they each contributing? Syo an actual box test, with full mag movements at several points. Is the optic actually sound, or just "moves".

We've all been there, so I don't mean this in any way derogatorily. Those are cheap bottom end scopes and mounts. It's more likely they had a bag day, than two different factories accidentally machining reverse can't into a receiver and going they both landed in your possession.

Cheers
Thanks Darkker, no offense taken. I appreciate your feedback.
I remeasured the rings, I get no more than .0005" difference between the two. However, my so called " zero MOA based did measure .004" difference end to end. I did not see that when measuring it on the gun. Its difficult to measure it precisely because of the concave bottom but I got consistently different measurements end to end off the gun. The average being .004"

Isn't offset something like .010" per foot though?

The scope tube measured right at 1" both ends. As far as the scope tracking to clicks input, I would say that is on. When I was making adjustments to zero it, I was going 20 clicks both ways and the POI tracked perfectly up and over at a 45deg angle til I got the windage zeroed, then continued up to get elevation zeroed.

, jeff
When I put a mirror on the scope and turn the turret I can see move at each click.
 

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Most respectfully, I mean it. There are five things to consider here, I'm not one of them, lol. Here's how I see it in the most simple manner possible.

1. The top of the receiver, mounting screw holes, positioned correctly, receiver milled correctly, checked and verified.

2. Ring bases, correct, flat to spec, front and rear known and positioned correctly, attached correctly to torque spec, checked and verified.

3. Rings, correct for bases and scope, front and rear oriented correctly, if required and torqued to spec, attached to scope correctly, checked and verified.

4. Use another scope of known quality and issue free, with both turrets zero'd, bore scope it for alignment issues, use a collimator, if one is available, see what adjustment or corrections are needed on your table, not at the range, refer to 1,2,3 above for solutions, which may include shims or a return of parts.

5. This is you. Triple check everything above, use a level and a straight edge, if and when you can? Don't glue or loctite anything until everything is known right. Don't leave the table for the range until it is right.

This is a mechanical/installation issue. There is nothing mysterious about it. There is the unknown which is frustrating.
There are a lot of other folks here who are light years ahead of me in the smarts department and their collective experience is invaluable and affordable. I suggest you listen to them. Stick with it and they well see you through to the end. Best of Luck and go bag a buck. :)
 

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The Hog Whisperer (Administrator)
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Get a straight dowel rod, 3 or 4 feet long, and mount is in the rings. See where it 'points' with the rings/bases on the gun.

Up/down might be hard to judge by the barrel taper, but left/right should be obvious if it's wrong.
 

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The Shadow (Moderator)
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1) I remeasured the rings, I get no more than .0005" difference between the two. However, my so called " zero MOA based did measure .004" difference end to end. I did not see that when measuring it on the gun. Its difficult to measure it precisely because of the concave bottom but I got consistently different measurements end to end off the gun. The average being .004"

Isn't offset something like .010" per foot though?

2) The scope tube measured right at 1" both ends. As far as the scope tracking to clicks input, I would say that is on. When I was making adjustments to zero it, I was going 20 clicks both ways and the POI tracked perfectly up and over at a 45deg angle til I got the windage zeroed, then continued up to get elevation zeroed.
1) No, WAAAAAY less than that. This is the long way around, but keeps scientific functions out of it.
Assume we are talking about a 20 MOA base:
20 * 1.047 / 3600 = 0.00581666666. This is fall per inch. Now multiply by the mounting length of your rail, assume a 7" rail length Ergo--> 0.00581666666 * 7 = 0.0349" difference in height from end to end. At the very least, try flipping your base around end-to-end, and see what results.

2) Again, did you change the magnification at various levels of adjustment; AND did you do it on something with standard grids?? When a MK-IV..... messed the bed on me, simply "looking through it", things were moving. When you actually grid, or box test it, it wasn't even close to accurate. Similarly, a brother had a tin can on one of his rifles, which tracked just fine..... Until you adjusted the magnification, and things went to left field. I've seen this where it doesn't appear to move with mag, but when you shoot; it most certainly did.

Cheers
 
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Discussion Starter · #25 ·
1) No, WAAAAAY less than that. This is the long way around, but keeps scientific functions out of it.
Assume we are talking about a 20 MOA base:
20 * 1.047 / 3600 = 0.00581666666. This is fall per inch. Now multiply by the mounting length of your rail, assume a 7" rail length Ergo--> 0.00581666666 * 7 = 0.0349" difference in height from end to end. At the very least, try flipping your base around end-to-end, and see what results.

2) Again, did you change the magnification at various levels of adjustment; AND did you do it on something with standard grids?? When a MK-IV..... messed the bed on me, simply "looking through it", things were moving. When you actually grid, or box test it, it wasn't even close to accurate. Similarly, a brother had a tin can on one of his rifles, which tracked just fine..... Until you adjusted the magnification, and things went to left field. I've seen this where it doesn't appear to move with mag, but when you shoot; it most certainly did.

Cheers
I appreciate everybody's experience and input. That is why I asked the question here. So, I say this with no disrespect to anyone. Being a Process Engineer for about 15 years I learned a bit about trouble shooting. Its a pretty simple process.
Identify each of the variables. Remove or replace each of the variables one at a time and look for impact on the problem.
My variables are
1.Me
2.The gun
3.The base
4.The rings
5.The scope
In my mind other things like weather, wind, temp etc are negated by the fact that I am grouping well.

Scope - I replaced the scope with another new out of the box Leupold scope. Same results - I ruled out the scope
Base - part of the issue for sure since it measures .004" different end to end. The thicker end was mounted towards the muzzle which contributes to the problem. I will turn it around and shoot the gun again to see impact.
Rings - They measure virtually the same , .0005" difference. But I have a set of Weaver rings that should be the correct height. I will try those.
Me - I am perfect as is, ( not changing me ) :)
The gun - with my skill / available tools, there is nothing I can, or would want to, do here.

I will give an update when I make these changes and try them.
 

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Unless the barrel was cut off by hacksaw at an angle and left un-crowned, it's not the rifle's fault. Two scopes point the same way. Its not the scope's fault.
It can ONLY be the mounts and rings. When the gun shoots way low, the scope is pointed up-hill compared to the rifle. That means the rear base was put on the front. Way to the right means the dovetails don't match up. (duh)
THAT is your problem. The bases are installed backwards.
 

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Discussion Starter · #27 ·
Unless the barrel was cut off by hacksaw at an angle and left un-crowned, it's not the rifle's fault. Two scopes point the same way. Its not the scope's fault.
It can ONLY be the mounts and rings. When the gun shoots way low, the scope is pointed up-hill compared to the rifle. That means the rear base was put on the front. Way to the right means the dovetails don't match up. (duh)
THAT is your problem. The bases are installed backwards.
I appreciate everybody's experience and input. That is why I asked the question here. So, I say this with no disrespect to anyone. Being a Process Engineer for about 15 years I learned a bit about trouble shooting. Its a pretty simple process.
Identify each of the variables. Remove or replace each of the variables one at a time and look for impact on the problem.
My variables are
1.Me
2.The gun
3.The base
4.The rings
5.The scope
In my mind other things like weather, wind, temp etc are negated by the fact that I am grouping well.

Scope - I replaced the scope with another new out of the box Leupold scope. Same results - I ruled out the scope
Base - part of the issue for sure since it measures .004" different end to end. The thicker end was mounted towards the muzzle which contributes to the problem. I will turn it around and shoot the gun again to see impact.
Rings - They measure virtually the same , .0005" difference. But I have a set of Weaver rings that should be the correct height. I will try those.
Me - I am perfect as is, ( not changing me ) :)
The gun - with my skill / available tools, there is nothing I can, or would want to, do here.

I will give an update when I make these changes and try them.
So, I broke the rules but I made 2 changes and tried them. Ammo is expensive and I'm running out of patience.
1. I swung the base around with the thicker part towards the back
2. and put on a pair of Weaver rings that I had.
Group went from 18" over and 22" down to now at 11 1/2" over and 14" down
I went back and swapped the rings front to back, the group now hits 8 1/2" over and 20" down.

What does this tell me. ...... machine parts can't be trusted. And zero doesn't mean zero.
 

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Why are you shooting it? Take the bolt out and look through the barrel and compare that with what you see in the scope. It's called 'bore sighting'.
It takes nothing more complicated than a yard stick to align the rings and make sure they're straight. I feel sorry for that poor Leupold if you're cinching it down in out of level rings! :eek:
 
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I'd suggest that you purchase a decent, mechanical boresighter (collimator). I've used one for 30yrs and it has saved me tons of $ in wasted ammo. I'm online? with your BAR set-up (I've owned 5 BARs without issue).

I'm not sure why you're so concerned about a large, initial correction on a newly scoped, new rifle. If the scope can zero, simply zero it. As far as using a lot of adjustment giving you poor performance from said scope, that's a new one on me. I've never, ever heard that in 50+ years of shooting many rifles.

Scopes today are manufactured with a lot of adjustment range, use it. As a last comment, I had a strange issue sighting a Sako in this season as well. It's an excellent shooter and was sighted in last season. I decided to use different ammo this season, so simply placed my target @ 100yds to get it done. 1st shot, checked and lo and behold, no hole in the 2'x2' Target board.

Like I said nice rifle, good scope previously dead on 1.5" high @ 100. I scratched my head for a minute and then moved my board to 50. Shot one and......lol and behold, 6" high @ 50, so it was at least 1' high and completely off the target board on the first shot. I promptly made that HUGE correction and had it sighted in sub MOA in a few more shots.

I see no reason to not use or rely on a rifle scope combination because it used a lot of the available correction range. Some folks even like 30mm scopes simply because they typically offer more adjustment range when mounted.

Best of luck and I hope you get it all straightened out soon and easily. 👍
 

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Discussion Starter · #30 ·
I'd suggest that you purchase a decent, mechanical boresighter (collimator). I've used one for 30yrs and it has saved me tons of $ in wasted ammo. I'm online? with your BAR set-up (I've owned 5 BARs without issue).

I'm not sure why you're so concerned about a large, initial correction on a newly scoped, new rifle. If the scope can zero, simply zero it. As far as using a lot of adjustment giving you poor performance from said scope, that's a new one on me. I've never, ever heard that in 50+ years of shooting many rifles.

Scopes today are manufactured with a lot of adjustment range, use it. As a last comment, I had a strange issue sighting a Sako in this season as well. It's an excellent shooter and was sighted in last season. I decided to use different ammo this season, so simply placed my target @ 100yds to get it done. 1st shot, checked and lo and behold, no hole in the 2'x2' Target board.

Like I said nice rifle, good scope previously dead on 1.5" high @ 100. I scratched my head for a minute and then moved my board to 50. Shot one and......lol and behold, 6" high @ 50, so it was at least 1' high and completely off the target board on the first shot. I promptly made that HUGE correction and had it sighted in sub MOA in a few more shots.

I see no reason to not use or rely on a rifle scope combination because it used a lot of the available correction range. Some folks even like 30mm scopes simply because they typically offer more adjustment range when mounted.

Best of luck and I hope you get it all straightened out soon and easily. 👍
I definitely need a bore sighter. Thanks Tn
 

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I'll start by saying ...don't take anything I say as an insult, just trying to help figure out a perplexing problem. What all have said so far about scope mounting makes sense. But, back in post #8 you make a passing reference to a Remington 7400 "that also had this problem.". That make three different rifles that have an extraordinary amount of POA to POI variation that is way 'off the norm'. I'd say for that to happen three times would make you a very unlucky person indeed.
I don't know what you mean (how to assess or quantify) by your opening statement that "I'm relatively new to shooting / setting up rifles." I kinda think you are doing something wrong, besides it being a mechanical issue with the scopes and mounts. As opposed to trying to describe and 'troubleshoot' in written form, have you had anyone physically handle and look over your set up? Perhaps some photos of your rifles with scope mounted could aid in the diagnosis.
Thus far, no one has mentioned bedding, stock pressure on barrel, etc. Again though, for three different rifles, all having different stock to metal fitting, it's unlikely they would all exhibit that amount of 'off aim' impact, especially while obtaining good groups. Nothing is making sense!
 

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Way back in my younger years, before we had a lot of things we have today, we’d get a rifle/rings/base combo that would shoot too high or too low and we’d just shim it. Shot some of those guns for years and never gave it another thought. It’s nice to have everything just fall into place, but sometimes it just doesn’t. I wouldn’t be inclined to just send it back. Based on all of the OP’s comments I think there’s a degree of operator error here somewhere. Don’t take it wrong OP, see if you can find someone who’s really experienced who can take a look at your gun hands-on. It’s pretty hard sometimes to fix these things with a keyboard. I think everyone’s trying to help you but if you can, get someone you know at the range or something to take a look at it. I also have to agree about the comments about not worrying about all the adjustment you’re using up. Unless you’re hitting a hard stop, or are very close, it’s not going to be a problem. Good luck with this.
 

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The Hog Whisperer (Administrator)
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Yup, shim it. With a one-piece base, that should solve the problem to shim it at the rear. With two-piece bases, it would be best to either find some rings that let the scope 'float' a bit in them (e.g. the Burris rings with the inserts) or lap some rings so the scope isn't in a bind. And agreed that you should be able to sort most of this out, bore-sighting it. I take the action out of the stock (if necessary) and hold it in a bench vise in the garage, with some convenient aiming point. Isn't too hard once you get the knack of it.

Best of luck.
 
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"Always low groups" seems to indicate the bell of the scope is hitting the barrel .
A good, calibrated, Mark One eyeball should solve the problem. ;)
 
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You have no idea how lucky your are or can be. I gave you a strong hint. JBelk followed up with strong advice. Do what Mr. Belk says, exactly. He knows. Your choice?
 

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Discussion Starter · #36 ·
I'll start by saying ...don't take anything I say as an insult, just trying to help figure out a perplexing problem. What all have said so far about scope mounting makes sense. But, back in post #8 you make a passing reference to a Remington 7400 "that also had this problem.". That make three different rifles that have an extraordinary amount of POA to POI variation that is way 'off the norm'. I'd say for that to happen three times would make you a very unlucky person indeed.
I don't know what you mean (how to assess or quantify) by your opening statement that "I'm relatively new to shooting / setting up rifles." I kinda think you are doing something wrong, besides it being a mechanical issue with the scopes and mounts. As opposed to trying to describe and 'troubleshoot' in written form, have you had anyone physically handle and look over your set up? Perhaps some photos of your rifles with scope mounted could aid in the diagnosis.
Thus far, no one has mentioned bedding, stock pressure on barrel, etc. Again though, for three different rifles, all having different stock to metal fitting, it's unlikely they would all exhibit that amount of 'off aim' impact, especially while obtaining good groups. Nothing is making sense!
Not a stretch to go there I suppose. Im not offended, but in my defense here goes.
Just a bit more on the problem with the 7400. I bought is used from Gunbroker from a seller that turned out to be a Pawn shop somewhere, I forget. I didnt shoot it until the 3 day " warranty " had passed so I now owned it. It had a cheap scope on it and I wanted to replace it with a Leupold. I took the rings off and found scotch tape in them on one end. I bought a new Leupold dovetail base and rings. I Didnt bore sight it, didnt have one. ( it too a semi automatic, you cant take the bolt out and eye down the barrel ). I started shooting it off my bench at 100 yards, just cuz it was easier. Shooting at the center on a 4x4 sheet of plywood. Nothing, moved up to 40 yards, nothing. Had to move up to 20 feet to find that I was hitting waaaay low. Adjusted my aim to find I was hitting 3 1/2 feet below POA.
Tried different scope, rings etc. Did some research but shimming is real sketchy in my opinion. getting both rings to be on the same plane with different size shims under them doesn't seem possible to me. in the end I had a Leupold solid 1 peice base milled down at a machine shop to take .030" off the bottom at one end at a taper to zero on the other, I then used the Burris Signature rings and add another .025" or .035" ( I cant remember ) offset with the inserts. I finished it off by using the turret and made adjustments to finally get it to hit zero.
You probably dont believe that but thats the way it happened.

As for the second, My new Savage 110, I had a similar experience. All new rings / bases, a new scope. I sold the last scope with the gun. I explained the whole deal to the buyer and he didnt mind. He had shimmed other guns before he said. Anyway, the savage shot so far off, over and down that I took it apart and started looking at different rings that I had etc. You could actually see the scope off alignment with the barrel of the gun by eye on the bench. I took the scope off and layed a long rigid stainless steel rod that I had in the rings, you could actually see the rod misalinged by a lot at the end of the barrel. Sent it back to Savage. They still have it.

So when I try this new BAR and see the Point of impact this far off. Obviously I was not happy.
Now you dont know me but I'm not clueless. If there was a glaring problem like the scope touching the barrel I would not even use rings like that. My only experience though is what I have read and a couple of older buddies with a lot more experience. So my problem is that I dont have a lot of experience outside of about 6 rifles. So I dont know what " normal sight in " is for most people. Hence the title of this string.
Anyway, through this I did learn that rings and bases are not made very precisely. And can change point of impact a lot more that I realized. You shouldnt be able to change rings and bases for what is supposed to be like equipment ( all with no offset , no front or rear etc ) and see 6" difference in point of impact.

So, I bought a new set of 1 peice rings/bases from Browning. If I get within 12" or so of the target I am gonna use the turrets and make the adjustments and be done with it. If its still 2 feet off, them I am gonna send it back to Browning with the new rings and have them look at it.

I have a Rem 7400 in 30-06 that is setup perfectly and will shoot sub 1" groups with my handloads. I have another new Savage model 11 ( in right hand ) that setup easily and shoots 1 " groups with Federal Fusion factory rounds right out of the box. Mini 14 , same. Never saw this problem with either of those guns or the rings bases I used on them.

Thanks for all of your feedback. I know its hard to tell someone they are wrong without sounding condescending but most of you did that. LOL

Thanks, jeff
 

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The Hog Whisperer (Administrator)
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Dang, you've got all the luck! 7400s and Salvages aren't really the ultimate in fine gunmaking; but I'd expect better from the BAR.

If you can figure out how much to shim a one-piece base, then 'bedding' it to the top of the receiver with epoxy would help keep thing from being in a bind. With two piece bases, I'd for sure lap the rings afterwards, or use rings with the inserts that 'float' a bit.

Wonder if any of the guns had a bent barrel.
 

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What was said earlier about a visual bore site or using and inexpensive laser bore sighter would confirm whether it was a gun or optics problem. Look at your muzzle crown for a major burr and stand back and look at your whole set up from several different angles it should be something obvious. If you have to adjust and shim as much as your saying is not the correct way to do it and the gun will probably be off at ranges other than what it was zeroed at. I have zeroed both new and used guns more times than I can count-if I ran into problems it was almost always self induced.
 

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Well Jeff, I think you sold yourself a little short in your opening post, seems to me you do have some experience and knowledge on the subject. So, after 36 posts, the simply answer to your opening question is; While it can happen, it is not normal, at all. Just my opinion. Also, I've never thought it's a good idea to 'use up' all of the scope adjustment available, either windage or elevation. The closer you get to the maximum 'edge' of adjustment the greater the risk of optical distortion exists. The impact is greater on higher powered benchrest type scopes with their narrow field of view. Also maxing out the adjustments can introduce mechanical issues, stresses and such.
 

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The Shadow (Moderator)
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If you can figure out how much to shim a one-piece base, then 'bedding' it to the top of the receiver with epoxy would help keep thing from being in a bind.
I gave him the math to be able to figure that. The question is will he be redneck enough to do the solution, or is he going to be chicken and ask if Someone else had done it they way first. 😉😆😆😆
 
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