Here's a way to tell if your rifle's crown has a problem:
Clean the muzzle off real good so that it shines, then shoot 10-15 rounds. Open the gun and set it on a rest or something so you can examine the crown.
Look closely at the muzzle, there should be a star-shaped pattern on it. This pattern is made by propellant gasses depositing fouling on the muzzle's surface as the heel of the bullets exited the bore.
This pattern should be even, sharply defined and centered on the bore. If it isn't, you have a less-than-perfect crown. If the "petals" of the star are not of equal length, or if the pattern itself is off-center, it could be that the face of the muzzle is not plumb with the axis of the bore. This can affect the bullet's stability and consequently it's flight. If the pattern is fuzzy anywhere it could be a burr or other roughness in the surface of the muzzle/crown, like a burr.
Anyway, analyzing this fouling pattern can tell you alot about your rifle's crown
HTH
Mike