Flying with firearms and ammo is not really as big a deal as it is made out to be. I make a yearly 6000 mile trip through the states once a year traveling with two pistols and ammo and the airlines pretty much have things worked out. I have always used one of the factory hard boxes which the pistol was shipped with. I get a key lock from Home Depot and lock the pistols inside the case within my suitcase. Most airlines prefer ammo to be in their factory boxes so I pack my 11 pounds of ammo in the factory boxes and put it inside the suitcase.
When you check in ask one of the information people if you need to check in at a special location if checking a firearm. Some airlines want you to, some don't. There is nothing worse than waiting in a long line and when you get to the front of the line you are told you should have gone to a different check-in site.
You need to declare the pistol and ammo to the check-in attendant. Sometimes they will take you somewhere where you can show them that the firearm is unloaded, most times they will take your word for it. They will give you a firearms declaration tag that they will put with your pistols inside the suitcase.
Then it is off to TSA screening. Every time the TSA people have taken all my stuff out of the suitcase, opened the ammo boxes and pistol cases to inspect them. They then repack everything and have me lock up my pistol case and suitcase. The TSA folks seem pretty comfortable with the process also. After TSA clears the bags they are taken back to the airline counter and put on the belt for the plane.
One note- if you are landing in some locations where high cap mags are not allowed you might want to mail them to yourself ahead of time. I travel through Hawaii and California often and mags over ten rounds capacity can cause legal problems (I think the same is true for other states, like New Jersey. One way to check is to look at the website Handgunlaw.us
). I usually carry .45's and the mags hold less than ten rounds so I am OK. When I traveled with my Glock 19 this last summer I had to mail the 15 rounds to myself before I transited through Hawaii.
So pack your stuff, check your pistols and ammo and have a good trip.
best wishes- oldandslow