The difference between the 22” and 24” barrels will be virtually undetectable by you or the animal you shoot with the rifle! The balance will not be detectable between the two either! IMO you shouldn’t sweat the small stuff. Just get your rifle and shoot what ever Canada has to offer.

On the scope mount, if the smith you sent the rifle too is puzzled with how to mount a scope on your double rifle you need to send it to someone else! A full 80% of the GOOD gunsmiths outside Europe simply do not understand how a double rifle works, and sometimes make some very expensive mistakes when working on them!

First off any scope you mount on a S/S double rifle needs to be mounted in Quick Detach mounts, and mounted as low as is possible! The scope, rings, and mounts must be as light as possible as well! The reasons for these things are because of the way the S/S double rifle goes about performing regulation when fired! With the sights aligned on the aiming point when the trigger is pulled, the barrels are looking at different places that the sights, with the RIGHT barrel pointing at a place that is to the LEFT, and LOW, looking through the bore of the barrel, while the LEFT barrel will be looking at a place that is LOW and RIGHT looking through the bore of that barrel.

When the RIGHT barrel is fired the rifle recoils UP, and to the RIGHT, and the LEFT barrel when fired recoils UP, and to the LEFT. When the bullet exits the muzzle after what we call "BARREL TIME" the barrel being fired will be then pointing to a spot on the target that is just on it's own side of the aiming point of the sights. Now anything that retards or accelerates the "FLIP" of the fired barrel will result in effecting regulation. The weight, and height of the scope above the barrels adversely affect the muzzle flip to one degree or another! So not only where the scope is mounted, but how far forward, and how high makes a lot of difference as to how well the rifle will recoil with that scope mounted.

Zeroing the scope once mounted is also something most do not understand and is different from a single barrel rifle! The normal way of zeroing a scope on a single barreled rifle is to fire about three shot on the target, then move the scope from the point of aim over to the center of that three shot group! The difference is with a double rifle you need to adjust the scope to a point half way between the CENTERS of two barrel’s individual groups! This is so that the zeroed aiming point is half way between the barrel’s individual groups, pointing at a new aiming point that is now the center of two individual barrel groups to form a composite group of both barrels on the target!