Zeroing problem

Hales Smut

Well-Known Member
I try to zero an Optisan Viper 4-16x50 on my 243 . I use mounts similar to the Leupold high mounts , = 12 mm from the the top of the Warne base to the below side of the ring.
Started shooting at 25m at a cardboard from 60x60 cm ( 24x24 " ) . I am still about 8" high and ran out of adjustments. Never had this with any European scope.
Shimming seems the answer, but how to do it and what to use ?
 

stalkerboydy

Well-Known Member
I try to zero an Optisan Viper 4-16x50 on my 243 . I use mounts similar to the Leupold high mounts , = 12 mm from the the top of the Warne base to the below side of the ring.
Started shooting at 25m at a cardboard from 60x60 cm ( 24x24 " ) . I am still about 8" high and ran out of adjustments. Never had this with any European scope.
Shimming seems the answer, but how to do it and what to use ?
I've got a Scope the same as. It's been on .25-06 to.17HMR to .300Win-Mag and now back on the .17HMR and I've never experienced the problem you have. A right pain i know but wind BOTH turrets in without over winding then wind both fully out but County turns. Divide the number by half then wind both turrets in by the half number and and now you will have the Cross Hairs fully centred.
Thankfully following that advice sorted a similar problem to yours. I personally know a few people do this to any new scope they mount
 

Yorric

Well-Known Member
Hales
It sounds like you have a bad scope ( poor manufacturing, bent tube or broken inside) or the rings are wrong for your rifle or badly fitted. (Rear ring could be set too high on the receiver to give your symptoms if it is too high by not being fully seated on the action).
Check the mount fitting/seating & maybe try a "European scope" or another proven scope if you have one available.

Ian
 

Hales Smut

Well-Known Member
I've got a Scope the same as. It's been on .25-06 to.17HMR to .300Win-Mag and now back on the .17HMR and I've never experienced the problem you have. A right pain i know but wind BOTH turrets in without over winding then wind both fully out but County turns. Divide the number by half then wind both turrets in by the half number and and now you will have the Cross Hairs fully centred.
Thankfully following that advice sorted a similar problem to yours. I personally know a few people do this to any new scope they mount
Did this already. Windage is fine, so I didn't count these clickcs. Elevation has 648 clicks. ( 13x48) + 24. Did put it to centre this evening and put the Zero notch at this point. Will write down the adjustments that I make in the future. 1/8" per click at 100m .
It's hard to change scopes. My other scope is a Kahles 6x42 with 26 mm tube. Never even considered running out of adjustments. Have used the Kahles and a Swarovski 1.5-6x42 and always plenty of adjustment.
Want to use this scope for a particular purpose for wich they say they are better than European scopes.
My Kahles was on this rifle with Norlyx low mounts ( 4 mm) . Fitted well but to low for being comfortable. I am using a PSE stock and they seem to be made for bigger modern scopes. A 42mm scope in low mounts is to low on a PSE stock and my Rem 700.
Thanks for the info.
 

AN DU RU FOX

Well-Known Member
try medium if all else fails,i read somewhere that even the windage can alter the vertical if the windage is allready over adjusted, not sure on that but sounds to me like those rings are way to high,imho
 

hairlesshunter

Well-Known Member
First I would recalibrate the scope count the number of clicks from high to low then half to recalibrate then try zero zeroing again
 

philip

Well-Known Member
I've just set a scope up with a similar problem for a shooting buddy this afternoon in between mending high seats, I reset the scope setting back to mid way on both elevation and windage, when done I used a collimator bore sight to get a measure of either drop or elevation required and installed a shim ( in this instance on the rear mount) to fit to bring the reticule into line, it's a little fiddly, but this afternoon the rifle shot clover leaf in the bull at a 100 yds - job done.

Good luck

phil
 

Hales Smut

Well-Known Member
Your haven't got the front mount on the rear do You?
Doesn't seem to be any diffrence. But changed them yesterday to be sure. After removing the mounts , changing them from rear to front and mounting again there was only a diffence from about 1" in windage.
So pretty good return to zero, for fixed mounts.
 

Conure

Well-Known Member
The issue with using shims is that it introduces tensions by bending the scop body tube. This is why Americans often lap their scope mounts to remove any tensions in the scope body. Try just doing up the front ring and check if there is any clearence under the scope tube and the mount lower. The do the same for the other ring. You might find your problem then.
 

Mr. Gain

Well-Known Member
I absolutely agree -as has been suggested already- that you should check the concentricity of your mounts, and invest in a collimator as a more accurate way to bore-sight and confirm zero subsequently.Before shimming, however, I would make the following additional check on the scope.

  1. Place a large target card downrange (25m should be enough) and mark it with two points spaced vertically to match the total nominal vertical adjustment range of the scope and a central point to mark the notional optical centre.
  2. Then place the rifle in a rest, dial the scope to centre it optically, and align it with the central point on the card.
  3. Now, without allowing the rifle to move, dial the scope all the way up and then all the way down.
  4. Clearly, if it reaches the top and bottom points the inner tube is being moved by the turrets as it should.
  5. If the scope is unable to track onto either point then something is not right internally and the scope should be returned for replacement or repair or binned.
HTH
 

J111

Well-Known Member
Centre the scope for elevation and windage, then bore sight it and see how far of it is. What rifle is it?
 

Hales Smut

Well-Known Member
Thanks for the help. I recalibrated the scope ( centre the scope for elevation and windage ) . Fired a shot and was 1" high and 3" right at 25m . Don't ask me why. In 3 shots I was just below my point of aim at 25m. I did two test shots at 80m and was 12-13m high, windage perfect. Along the Norma catalogue this shoud make a zero from about 160/170 m. 75 gr HDY in a 243 , Rem 700 , PSE stock.
Going to give it a try soon.
 

Top