I see a lot of barrels with damage at the muzzle because they have been fired with dust and debris in the barrel.
When firearms are stored standing up, dust accumulates in the muzzle, just like it settles on the front lens of your scope...when it gets so bad you notice it; rubbing that dust away with your shirttail damages the coating of the lens and affects the light gathering ability of the scope.
When you place your gun in and out of a soft case, dust accumulates in the muzzle.
If the rifle is fired with this dust in it, it has the effect of lightly sandblasting the bore in the area with the dust. It accelerates the wear and affects the accuracy eventually.
I inspect the bore of my rifle and then cover the muzzle with either a layer of masking tape or a layer of electricians tape and I use lens covers on my scope.
A taped muzzle protects the bore and point of impact does not change.
As previously mentioned you can wrap a little extra replacement tape around the barrel.