Unexpected zeroing problem

[rancidtom]

Soft shims used correctly will not bend a scope tube, hard shims will unless the screws are left too slack to gip the scope properly and seeing as this is a recoiling rifle it can cause crimping and bending to the scope tube if done tight enough to prevent the scope moving in the mounts.
I stroungly suspect a barrel misalignment problem or quite possibly the rear of the mount has been fitted OVER the recoil arrestor stop thus not allowingg it to clamp correctly on the scope rails. A one piece mount will need to be mounted in front of the arrestor stop.

[NigelG]

Have you got a long straight edge, you can use a length of string pulled tight. lay rifle down and place straight edge along centre of barrel. If it starts to work its way to the top of the action, your barrel is drooping. In a gun shop years ago and a dad and son came in and complained they could zero it. The droop was so obvious just by being further away from it and looking at it

[Steyr]

Have you got a long straight edge, you can use a length of string pulled tight. lay rifle down and place straight edge along centre of barrel. If it starts to work its way to the top of the action, your barrel is drooping. In a gun shop years ago and a dad and son came in and complained they could zero it. The droop was so obvious just by being further away from it and looking at it

You can also use a straight edge on the internal bottom half of the mounts to see if the steel edge runs flat or if it steps or if it pitches away. Both should be flat and no gaps on either ring.

Banana barrels should be easier to spot

[angrybear]

Soft shims used correctly will not bend a scope tube, hard shims will unless the screws are left too slack to gip the scope properly and seeing as this is a recoiling rifle it can cause crimping and bending to the scope tube if done tight enough to prevent the scope moving in the mounts.
I stroungly suspect a barrel misalignment problem or quite possibly the rear of the mount has been fitted OVER the recoil arrestor stop thus not allowingg it to clamp correctly on the scope rails. A one piece mount will need to be mounted in front of the arrestor stop.

Or the mount itself has a recoil pin which is protruding so the mount cannot seat on the rail correctly, OP states the clamp is on the left which would put the recoil pin under the front scope strap, if the pin is proud it would be raising the scope objective thus raising the POA.

[Portzy]

I removed the recoil pin before fitting the mount, and I also removed some time ago the riser thingy which had the torx stud attached to it. That said, the way I have originally fitted the mount does put the empty recoil pin hole under the front strap so maybe there is a specific way that the mount should go?

As I intended, this afternoon I spun the mount round and refit the scope, I just need to square and level things then get out into the garden.

[Steyr]

Soft shims used correctly will not bend a scope tube, hard shims will unless the screws are left too slack to gip the scope properly and seeing as this is a recoiling rifle it can cause crimping and bending to the scope tube if done tight enough to prevent the scope moving in the mounts.
I stroungly suspect a barrel misalignment problem or quite possibly the rear of the mount has been fitted OVER the recoil arrestor stop thus not allowingg it to clamp correctly on the scope rails. A one piece mount will need to be mounted in front of the arrestor stop.

How so....one end is at zero and the shimmed end is at (x) difference. Unless both points are level, something is getting bent.