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Discussion Starter · #1 ·
I completed my project of restoring a 1944 Izhevsk ex-sniper. I put an original PU Scope on it and tapped the original mount holes since they lined up. Now that the scope is back on the weapon, I noticed that it is off center by about 2 feet to the right (view field) I was using my LBS kit and could not even see the dot. I lined up my center of mass using the barrel sights, and verified it with the scope, not even close. I also noticed that the scope itself is now mounted on an angle that bisects the barrel. To bring the scope back to center, do I file down the rear post where the locking screw is on the mount? Or is there a less damaging way? Maybe a longer front locking screw that is shimmed? Any suggested are welcomed.


Thanks!
 

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I completed my project of restoring a 1944 Izhevsk ex-sniper. I put an original PU Scope on it and tapped the original mount holes since they lined up. Now that the scope is back on the weapon, I noticed that it is off center by about 2 feet to the right (view field) I was using my LBS kit and could not even see the dot. I lined up my center of mass using the barrel sights, and verified it with the scope, not even close. I also noticed that the scope itself is now mounted on an angle that bisects the barrel. To bring the scope back to center, do I file down the rear post where the locking screw is on the mount? Or is there a less damaging way? Maybe a longer front locking screw that is shimmed? Any suggested are welcomed.


Thanks!
You shim or grind down the back two tabs of the scope mount, not the base.
 

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If I'm understanding correctly that the scope is "looking" 2 feet to the right (in other words, the rifle would shoot 2 feet to the left if you aimed at the target with the scope), assuming that the reticle is centered horizontally and that the mount is properly placed with both mount pads touching the base, the pads are going to have to be ground in order to line it up. I'd advise you to be absolutely sure before removing material, though, and be aware that you have to remove the correct amount of material proportionally from each pad in order to properly orient the scope above the bore. And a very small change in the pads makes quite a sizeable change in POI.
 

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Don't grind or shim anything yet.

Step 1: Shoot the rifle with irons at 100 meters (or yards if you have to) and drift the front sight to get your windage "on".

Step 2: Take note of where the POI is using the irons. This will be your reference point for setting up the scope.

Step 3: Set up the scope to match the irons. If you can't do it and keep the scope centered over the bore, THEN figure out if you need to shim/grind anything. If you do, go VERY slowly during this process, especially if grinding.

Laser boresighters have always been more trouble than they're worth for me. I've used the above method on several PUs (and many other scoped rifles) and it's never failed me. The most important thing to remember is that a laser shoots in a straight line. Bullets don't. So, the two will rarely have anything in common.
 

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Discussion Starter · #6 ·
Thanks all. I will double check all the screws before I put anything to a grinder. I am certain the the base is flush and I may be able to shim the forward screw, I recall it going a bit to deep where the bolt would not go passed.
 

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Discussion Starter · #7 ·
I know I need to fire some registration rounds, but I know that the sight picture I currently have is terrible since I should at least see the red dot in my FOV through the optic. Here's a pic of what I see
 

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Almost looks like it is the mount/mounting rings and not the base. The horizontal plane of the mount, on the left side, looks almost straight but the front mounting ring seems to be warped pushing the scope to the right. Just a uneducated guess. Is that an Accumounts mount and base? I had the same problem with a CAI reproduction PU until I purchased the accumounts setup and then everything was just fine. The CAI alloy mount and base just didn't get it done.
 

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Discussion Starter · #9 ·
What about grinding some of the rear post down on the base?

 

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Absolutely do what Joop says!!!

Please post another picture of the rear of your base on the rifle. That big "post" sticking out by your rear screw doesn't look like it should be there -I think you have a pin in the way of a proper fit. The rear of your mount isn't going back into the base flush against the rifle like it should.

Laser boresighters are often absurdly wrong. I have no use for them on Mosins as both real boresighting and iron sight witnessing do a lot better in most cases.

Try actual boresighting - sighting through the bore with bolt removed at a distant object and, without moving the rifle, see where your scope is aligned. Then do exactly the same over the iron sights, holding the rifle steady and moving to see where the scope lines up.

Those Red Army snipers weren't dumb -they could always line up their scopes to get on paper with the iron sights or use them for close quarter fighting or backup if the scope got broken.


Don't grind or shim anything yet.

Step 1: Shoot the rifle with irons at 100 meters (or yards if you have to) and drift the front sight to get your windage "on".

Step 2: Take note of where the POI is using the irons. This will be your reference point for setting up the scope.

Step 3: Set up the scope to match the irons. If you can't do it and keep the scope centered over the bore, THEN figure out if you need to shim/grind anything. If you do, go VERY slowly during this process, especially if grinding.

Laser boresighters have always been more trouble than they're worth for me. I've used the above method on several PUs (and many other scoped rifles) and it's never failed me. The most important thing to remember is that a laser shoots in a straight line. Bullets don't. So, the two will rarely have anything in common.
 

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Discussion Starter · #13 ·
Im at work now, but will post what pics I currently have. The pins protruding are fixed. They came like that on the base. The only way I can see getting them off would be cutting them which I hope I don't want to do. I found it odd that there are secondary plugged holes in the receiver and they seem to line up.

Here is what I have so far.


The first pic is of the base after I shimmed the forward screw. Same problem. But from what I am seeing here, those pins that are protruding should be set into the receiver?
 

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ABSOLUTELY! Don't do anything until you deal with that rear pin-that's probably the source of your problem.
Me too, what Relic and Stalin's Ghost said. That pin is probably what is pushing the scope tube out of kilter. Those are alignment pins.
 

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Don't grind or shim anything yet.

Step 1: Shoot the rifle with irons at 100 meters (or yards if you have to) and drift the front sight to get your windage "on".

Step 2: Take note of where the POI is using the irons. This will be your reference point for setting up the scope.

Step 3: Set up the scope to match the irons. If you can't do it and keep the scope centered over the bore, THEN figure out if you need to shim/grind anything. If you do, go VERY slowly during this process, especially if grinding.

Laser boresighters have always been more trouble than they're worth for me. I've used the above method on several PUs (and many other scoped rifles) and it's never failed me. The most important thing to remember is that a laser shoots in a straight line. Bullets don't. So, the two will rarely have anything in common.
This is why I just sent a tractor trailer load of my scoped mosin rifles to you to set up for me !/lol
 

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Discussion Starter · #17 ·
Ok, that certainly explains the problem. Now, the diameter of the holes for the pins seems smaller then the screws. Also, these two posts appear that they will need to be cut from the base, then set through. They do not currently slide through at all.
 

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Discussion Starter · #19 ·
The pins, that are in front of and behind the base screws. Thats what I mean by posts. Because they are fixed, thats why I say posts. Sorry about that!
 
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