Thread: shimming scope rings confusion

Pretty sure I can't VC. I've shimmed up the front now cheers guys. I'll have sighting in on Friday hopefully. Fingers crossed.

Originally Posted by johnino

I've cut shims from a V can and aralditing them in but thought I'd still lap.

Er problem solved................get rid of the V can shim and swap for a tui can shim

Still a bit confused. Is your elevation wound fully down and you are still high or something else?

Tried swapping front ring to rear and rear to front? Maybe different hights.

get some Burris Signature Zee rings with inserts

is your scope 1 inch or 30mm tube ?

Originally Posted by ebf

get some Burris Signature Zee rings with inserts

is your scope 1 inch or 30mm tube ?

+1
They are a brilliant piece of kit in my opinion .
The only downside is that they don't make a Low mount , only Med and High .
All of my scopes except one have Burris Zee rings .
The other one uses old fashion Weaver rings ( the band type with screws on one side ) they are the lowest rings I could find to bring the scope right down on my Blaser 223 barrel . The cocking - safety just clears the scope by a couple of ciggee papers now . It's a low as you can get a scope on a R93 .
I only wish Burris would take note and produce a Low Zee mount .
When setting up a scope with the inserts I make sure the scope is centred in its adjustments and then adjusting the inserts Not the scope I bore sight it to as good as I can get it . Using this technique I've never had to adjust more than about 10 clicks maximum in any direction to be smack on at 200 .
I highly recommend the Burris rings with inserts .


Ken

25mm. If this doesn't work I may need to. I wonder what thickness of shim can be fitted b4 farking the scope?

Originally Posted by johnino

25mm. If this doesn't work I may need to. I wonder what thickness of shim can be fitted b4 farking the scope?

ok, i have some +/-10 and +/-5 inserts for you if you get the burris rings. used +/-20s on my FTR rifle and gained a LOT of dial. depends on how far the rings are apart, if I remember correctly if they are about 3.5 - 3.75 inches apart, you will gain the full amount.

i've had no issues with them, they seem to hold the scope tight.

Originally Posted by ebf

ok, i have some +/-10 and +/-5 inserts for you if you get the burris rings. used +/-20s on my FTR rifle and gained a LOT of dial. depends on how far the rings are apart, if I remember correctly if they are about 3.5 - 3.75 inches apart, you will gain the full amount.

i've had no issues with them, they seem to hold the scope tight.

Cheers EBF. Currently got standard rings Leupold/Burris (not sure) definitely on Burris bases with windage screws on rear. Bases are 3.7" apart.

I just re-read your original post.

Sorry, I fucked up. @Shamus was right. Shim the front ring ... My bad ...

Still doesn't make sense, if the turret is wound all the way anti clockwise it is at max up adjustment, (clockwise left and down), therefore to bring it down just turn the turret clockwise? Or am I misunderstanding the explanation?

Yes, you shim the front mount. You work out how much you need to shim with a bit of trigonometry.

h = d x tangent(MOA/60)

Where:
Your calculator is set in degrees
h = the thickness of the shim you need
d = the distance between your scope mounts
MOA = the number of MOA you want to shift the point of impact

If you want the shim thickness in inchs then measure the distance between your scope mounts in inchs. Works for any units including mm.

Cheers Gillie. Good to have the formula. So can we work backwards?
h/d=tangent?
e.g. My shim is 0.00787", distance between rings is 3.69"
So 0.00787/3.69=0.00213279.
If that's right how does the answer relate to MOA?

So if you rearrange it you get something like:
h = 0.00787"
d = 3.69"
MOA = 60 x ArcTangent(h/d) = about 7.3MOA or about 7.5 inchs at 100 yards.

Interesting development. I put two shims (0.1mm thick each) from the V can on the front and put scope back in place and screwed rings together. Farkin awful! The magnification was all but impossible to turn, meaning tube was distorted. Took it apart, removed one shim and stuck it back together. Better but not I'm still not comfortable. So the plan is now I'll araldite one shim on the rear and two on the front, once the glue's dry I'll run a reamer through to create the angle hopefully taking the pressure off the scope tube. If the araldite lets go after the scope's screwed down it doesn't matter. It's only needed to keep the shims in place during reaming and locking down. Main lesson learned: be so careful doing shite like this not to destroy a good scope.