The significance of the Crimean War is that hits by marksmen at greater than 500 yards become common. This was possible only because of the Enfield's conical shaped bullet. Back in the round ball days 600 yard hits were very few and far between.
With the Enfield it was possible to hit out to 1,000 yards. That's why it became the weapon of choice for the Confederate sharpshooter battalions (that is, the men who were issued target rifles like the Whitworth or the Kerr).
For more reading long range shooting in combat, go to the The High Road's black powder forum's thread on sharpshooter stories Here
Why people like modern inlines when the old Enfield firing the .577 minie or Pritchett ball can do better escapes me.