Scope packing?

[mrgeoff]

I am half a turn off running out of adjustment on my scope.
FWB300SU Mk1, with an older Bushnell Elite 4500 6-24x42 on top, running like this for 25m benchrest.

Think that as the tube is near the edge of adjustment, its jumping a little, so would like to try packing the scope to bring it more central.

Question is, how much packing should I try on the rear mount? (I see sportsmatch sell a tapered mount with 0.4mm, I guess the reach forward mount is 0.4mm lower than the rear mount?)



Thanks!

[Brian.Samson]

About 15 MOA usually

Two ways to do it - turn the turret down to it's lowest point and count clicks until you reach the top of the adjustment, then halve the number of clicks to centre your top turret in the middle of it's adjustment range (this won't be optically centred, but that doesn't matter).

Then re-zero your gun and count how many clicks you've had to dial to zero it.

divide the number of clicks you needed by 8 and that will tell you how many MOA you need for angled mounts.

If you measure the distance between the two mounts centres and you know the angle in MOA you could calculate how much packing you'll need in the rear mount by using OPP/ADJ = TAN of the MOA.


OR.....


Just put some packing in the rear mount (old film negative is good if you can find it). Add a couple of bits of negative to start with, if that doesn't give you enough, add a bit more.

I'd recommend the trial and error solution personally.