I think I just read a post some where by 400NitroExpress

explaining why the rounds from the right and left bbls

will spread to some degree when a scope is mounted on a

rifle and it had been regulated without a scope.

If you increase the velocity of the bullets by increasing

the powder charge a bit, will you bring the bullets back

to the origional convergance point, or at least TOWARD it?

BFJ, I haven't read the post you're speaking of by 400NitroExpress, but I'd bet my next retirement check he has it right! I can't think of anyone more qualified to tell why!

The scope mounting is most times detramental to the regulation, but that is usually
because the person mounting. or haveing it mounted makes some bad choices of scope, and mounts! What I nean by that is, the heavier a scope is the more it will effect the grouping. When one chooses a scope/mounts that are too heavy, the then mounts it too high as well, things go badly very quickly. The leverage on the barrel set's recoil arch works against the natural way it was regulated to recoil. Then for every tiny rise in hight above the bore of the rifle's barrels this torque is multiplied. So if one is to mount a scope on his double that wasn't fitted with one from the maker,he must choose the lightest scope, and mounts he can find, and mount it for enough eye relief, and as far forward as the E.R. will allow, and finally mount it as low as sighting will allow. If all that is taken care of, the empact on regulation may not be much, if any. If it doesn't change very much, you are a lucky man, and some tweeking of loads may make the difference. I wouldn't go far enough to not be able to use the same loads for the irons as well!