scope is out of up elevation. time to shim?

frenchyguy

CGN Regular
Rating - 98.8%
79   1   0
Location
New Brunswick
ok, i have exhausted all the check points, and have determined i need to shim my scope base.at the max up adjustment it is on target, but i dont want to be at the max.do i shim the rear of the base? or the front?
 
Or consider getting a scope with more adjustment. I tried shimming last year to solve the same problem - hated it.
 
You can try the Burris signature rings with offset inserts. This will allow you the ability to do what Dogleg suggests without having to change your base. Also takes lapping out of the equation as the inserts kind of roll within to ring to align the scope on it's own, also doesn't mark your scope.

Here is a link to how the offset rings will effect your elevation change.

http://bulletin.accurateshooter.com...e-rings-calculating-actual-elevation-changes/
 
The real solution is to buy a 20 or 25 MOA base not shim.

But check that there isn't something wrong with your set up. A normal set of hunting rings/base and scope should put you on paper a 100 yards.

The 20 MOA bases are used for shooting long range to get more elevation out of your scope and will not help you if your scope is broken or your rings or base is out-of-wack.
 
If you don't have far to go, you can try switching the front and rear bases, and then the front and read rings. You want to get the thickest base and highest ring at the back.
 
The real solution is to buy a 20 or 25 MOA base not shim.

But check that there isn't something wrong with your set up. A normal set of hunting rings/base and scope should put you on paper a 100 yards.

The 20 MOA bases are used for shooting long range to get more elevation out of your scope and will not help you if your scope is broken or your rings or base is out-of-wack.

It would be nice if things were simple, but since they seldom are I stuck to answering the question as asked.
The answer isn't to use a 1000 yard solution for a 100 yard problem. If the receiver is out of spec, then the 20 MOA rail should be also be shimmed or bedded to correct for it. Bending the rail with the mounting screws or flexing the action with one of the bridge girderlike steel rails is tradeing one problem for another.
A scope with more adjustment would get him on paper, but doesn't address that something is out of whack, and there is more then likely a scope body that is being twisted to accomodate it.

Mounting problems aren't hard to sort out when all the pieces are in your hand. When they aren't, its varying degrees of guesswork.
 
Dogleg,

I agree with you as I explained before that the 20 MOA base is for long range shooting. The 20 MOA base would be a band aid to mask the real problem as would the shims because they do the same thing. The only difference is that the solid base would put the scope rings on the same slope plain and that would be better because you wouldn't have to lap. (Most people don't have the tools to lap)

To shim a base is just a cheap junky way to do things.

But you are right that there is more wrong that we can't see.

Love
 
Think that we need to know at what distance you are trying to achieve or zero your scope at???



ok, i have exhausted all the check points, and have determined i need to shim my scope base.at the max up adjustment it is on target, but i dont want to be at the max.do i shim the rear of the base? or the front?
 
shimming is a very very bad solution, buy the right base, the right rings or a different scope. Shimming introduces unwanted torque on your rings and scope.
 
shimming is a very very bad solution, buy the right base, the right rings or a different scope. Shimming introduces unwanted torque on your rings and scope.

Won't have a problem if you stick to a one piece base, torqued to spec, and keep it to 1 or 2 beer can shims, they vary from 3thou at the top of the can to 6 at the bottom, held to +-.0001 before the die rings are replaced (sometimes more than once a day)
 
Dam.. I just want frenchyguy to post some pictures of this problem rifle so we can put an end to this. I'm sure we could figure this out with some nice close ups.

If he doesn't lets just assume that it's a Savage with a Tasco scope.
 
You would be right, if the scope and rings arrive out of spec. Shimming should be the last resort, but what do I know?

Its far more likely that the receiver is out of spec than the bases. Unless of course they're the wrong bases, which is entirely possible since the OP hasn't anounced the make of the rifle, type and part # of the bases or much of anything else. With all the pieces in hand its easy stuff.
 
Its far more likely that the receiver is out of spec than the bases. Unless of course they're the wrong bases, which is entirely possible since the OP hasn't anounced the make of the rifle, type and part # of the bases or much of anything else. With all the pieces in hand its easy stuff.

shimming out of spec hardware is still a bad fix, better to fix the hardware.
 
Check to make sure your mount/base is the correct one for the receiver you have. I had a similar problem and in the end, it was the base that was at issue. Cost $20 to get the right one and that was it. I would go with the easy solution first before you start shimming/devcon or mucking about. The cheaper the base, the more likelihood of issues as well.
 
Back
Top Bottom