Muzzleloader Black

Will my rubber muzzleloader bullet work at short range?
I recently loaded a black powder muzzleloader with an aerotip bullet. However the rubber on the base was a little bit scewed - Im wondering at short range will this be a problem?
The base of a bullet is the most critical part.It is the last thing to touch rifling as the bullet leaves the bore. It takes very little damage to wreak havoc on accuracy. The bullet may tumble not shoot worth a damn.
CVA Muzzleloader Black Powder 101 - Various Propellants