I have adjustable mounts and only use them for doing long distance groups with FAC guns to keep my scope crosshairs near the mechanical (and hopefully the optical) centre of the scope.
As I said above soft shims can work allowing the scope tube to cant front to back in the mounts but they have to be used accordingly both mounts, front and rear, also top and bottom to prevent distortion from the top half of the ring as well as elimination of the edge contact and possible crimping issue. Plastic shims are easy to make and if they are soft enough will allow a scope tube to stay straight with some elevation/declination between mounts. The down side to soft plastic shims is that they can't be considered a permanent solution especially not on a recoiling rifle.