What you're feeling is, obviously, the bore being slightly larger in diameter at the breech.
Is it normal? Yes and no. It's not designed that way but bores can vary in diameter. It greatly depends on the manufacturing process as to how consistent a barrel is. CF "match grade" barrels that are hand lapped and/or air gauged are held extremely tight tolerances. A run of the mill factory barrel, CF or ML, that's manufactured with no further checks can be less than ideal when it comes to consistency in bore diameter.
With that said, then have you ask "Is it a problem."
Probably not. It's far more critical for the bore to be even in diameter near and at the muzzle. This is where inconsistencies can have a far greater affect on accuracy.
The end all answer is "Does your ML shoot accurately enough?" If it doesn't then it's time to contact CVA and explain the problem.
If were my barrel, I'd do one check just to see how consistent the barrel is at the muzzle. Pull the breech plug, start a projectile from the muzzle, push it down halfway, then push it from the breech end out the barrel. If it felt good and it shot accurately ... I wouldn't sweat it.
