Yes. You are missingeffectsof differing the contact/pressure points on a barrel. Each re-positioning of the barreled action in the stock creates slightly different pressure points. When a load is fired, the barrel moves as the bullet makes its way through the bore. The amount and direction of that movement (as well as the barrels vibration pattern)will impact where the bullet strikes - with longer ranges showing greater effects of those changes. Similarly, a barrel that is not properly stress relieved will exhibit erratic behavior as the barrel's vibration and movement are too greatly effected by even minor changes in temperature. The hotter loads in use today also contribute to an exaggeration of these effects and make proper bedding more important.

You can easily see the effect by simply changing forearm pressure/hold on many two-piece stocked rifles. Some are ultra-sensitive to even the position of your hand.

Pillar bedding eliminates almost all the variation associated with barrel removal/reinstallation. I agree with Head on this one but have to say that inmost cases, accuracy and consistency gains are minimal and often negligible in hunting muzzleloaders. A careful and consistent reassembly of the rifle will eliminate most significant shifts. If such a method does not yield the consistency of POI that you desire, you might investigate free-floating or pillar bedding.