What he said. Also, some clarifications:
The firearm must be in a locked container. That locked container can be checked luggage by itself, or it can be placed inside of other, checked luggage.
IMX, there is no need to "call ahead" to the airline. It is the ticket counter agent that will provide you the declaration form to fill out, and who will handle/process your luggage, and calling ahead won't facilitate that process.
I've never had anyone "inspect" my declared/checked firearm. I merely showed it to the ticket counter agent when declaring it, then locked the case and placed the declaration form on top of it. TSA *may* further inspect the declared firearm, but I've never had that happen, going through IND.
Ammunition does not have to be in OEM packaging, but cannot be "bulk" packed (even if OEM packaged that way); it must be in packaging that holds/separates each round individually. Each airline sets its ammunition weight limit separately, but IMX, 11 pounds seems pretty standard.
It must be the airports that I typically go to but in my experience my firearm has been inspected 100% of the time. IND may not. And the call ahead is required by the airline I use if you check in online. Although again I have used a different airline in a different state then most of you. (Hawaiian Airlines, HNL)
So I would trust your experience in Indiana however be aware of the different protocols at other airports and airlines.