Contact your airline, as there are slight differences between them. The consistant rules are:
- Firearms must be unloaded
- Firearms must be in a locked, HARD case. A small (pistol) hard case can be put inside other luggage once it's been checked.
- Generally, only two firearms can be taken without additional charges.
- Ammo must either be in original factory boxes or in plastic "reloader" boxes, such as those sold by Midway.
- There is usually a limit on the amount of ammo, often by weight. I know one airline specifies "less than 11 lbs."
Again, check with the airline, as there may be additional issues. If someone tells you that firearms aren't allowed, ask to speak to a supervisor, as they are mistaken.
You'll have to show the person at the ticket counter that the gun is unloaded (usually they just glance in the case), and sign a document stating that they are unloaded. They cannot mark the case as containing firearms on the exterior, but may give you a tag that goes inside the case.
This is all routine stuff, and should not cause any problems.
-Troy