Scope not parallel to bore

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04-19-2011, 14:32
d_striker

Scope not parallel to bore

I mounted my scope on my SPS Tac AAC SD a couple of weeks ago. I noticed then that my scope was "cross eyed" and pointing slightly to the left.

I didn't think much of it then as I'm fairly new to long range shooting.

I'm not sure if the receiver holes weren't milled in line or if the EGW base is off.

What's the best (and cost effective) way of fixing this and getting my scope parallel to the bore?

Adjustable windage rings?
04-19-2011, 15:02
BPTactical

Well the first place to start is with the rifle. We need to make sure the mount holes for the base are axially aligned to the bore. If they are GTG then checking the base is the next step.
Were the rings aligned before mounting the scope?
Using adjustable rings is an absolute last resort.
How did you ascertain the scope is not aligned?
Has the rifle been bore-sighted?
04-19-2011, 15:08
d_striker

Quote:

Originally Posted by BPTactical

Well the first place to start is with the rifle. We need to make sure the mount holes for the base are axially aligned to the bore. If they are GTG then checking the base is the next step.
Were the rings aligned before mounting the scope?
Using adjustable rings is an absolute last resort.
How did you ascertain the scope is not aligned?
Has the rifle been bore-sighted?

I'm at work now and plan on taking it apart to examine the mount holes.

I don't have any scope alignment rods and was just excited to slap everything on, zero at 100, and shoot a match.

The axis mismatch is so severe that you can see it with the naked eye. That and I had to dial quite a bit of windage to get it zeroed.
04-23-2011, 01:37
Rinodods

What rings are you using?
04-23-2011, 11:03
d_striker

Burris xtr's.

The rings are good. It's either the base or mounting holes.
04-23-2011, 11:31
Rinodods

I thought the same about my set of xtr's. Turns out they were off center. A different set of rings was just fine. I've seen this same issue with three other sets of xtr's in the last couple weeks. Might be worth it to really look them hard. Mounted on a one piece base you could see mine were not in alignment. Hope maybe your set is better than mine was. They are going back.
04-23-2011, 12:04
d_striker

Quote:

Originally Posted by Rinodods

I thought the same about my set of xtr's. Turns out they were off center. A different set of rings was just fine. I've seen this same issue with three other sets of xtr's in the last couple weeks. Might be worth it to really look them hard. Mounted on a one piece base you could see mine were not in alignment. Hope maybe your set is better than mine was. They are going back.

I picked up a kokopelli accurizing kit. I used the alignment rods and played with the configuration of the rings and they would point off in the same direction, no matter the configuration every time. The rings themselves are aligned to each other fine.

I installed the rings on an ar flat top receiver and used the rods. Center rod pointed perfectly down the barrel. This is why I think it's either the base or holes.
04-23-2011, 12:28
Rinodods

Sorry to hear that actually. Hope it is your base then. Kinda sucks when your receiver is drilled wrong. Hope you get it worked out. Good luck.
04-23-2011, 23:03
jmg8550

The cheapest way to fix the problem is to get a set of Burris Signature Pos-Align rings with the concentric inserts. They work very well and are pretty inexpensive. I have used several XTR rings and have never had a problem with them. Do not lap aluminum rings, it will take the hard anodizing off and the rings will leave marks on the scope. Also, make sure you are torquing the ring caps and cross bolts properly or your scope can move in the rings. Burris XTR rings should be torqued to 20-25 inch pounds on the caps and 60-100 inch pounds on the cross bolts. The caps on the Signature rings should also be torqued to 20-25 inch pounds.
04-24-2011, 10:06
SA Friday

Quote:

Originally Posted by d_striker

I picked up a kokopelli accurizing kit. I used the alignment rods and played with the configuration of the rings and they would point off in the same direction, no matter the configuration every time. The rings themselves are aligned to each other fine.

I installed the rings on an ar flat top receiver and used the rods. Center rod pointed perfectly down the barrel. This is why I think it's either the base or holes.

Check the mounting holes on the top of the receiver. Take a yard stick and line up the holes and see if they are concentric with the barrel. If they are, its the mount and an easy fix.
04-24-2011, 10:39
d_striker

Quote:

Originally Posted by SA Friday

Check the mounting holes on the top of the receiver. Take a yard stick and line up the holes and see if they are concentric with the barrel. If they are, its the mount and an easy fix.

Thanks.
04-24-2011, 10:45
BPTactical

Quote:

Originally Posted by SA Friday

Check the mounting holes on the top of the receiver. Take a yard stick and line up the holes and see if they are concentric with the barrel. If they are, its the mount and an easy fix.

While the yardstick will give a pretty good "quick'n dirty" check of the receiver screw holes to get a good, accurate assessment it is going to take some precision measuring. You are talking thousandth's of an inch here.
Example- if the holes are out of axial alignment by one thousandth of an inch at the receiver, 10 inches from the leading hole the error is 10 thousandth's of an inch and it grows exponentially.
If the receiver holes are out of tolerance (which is not uncommon on Remington's) there are a couple of options. If the rifle is new send it back to Remington, if not we can fix it- if the misalignment is small enough the holes can be drilled and tapped for oversize screws. If the misalignment is severe the holes are filled by silver soldering threaded screw stubs in the old holes and redrilling/tapping new holes.

Check your PM's