DO NOT rely on your travel agent, you must contact both airlines personally and inform them 90 days in advance that you will have a firearm. BA is very firearm unfriendly in my experience, you must first be approved by them to transit a firearm with them which takes several days to a couple weeks. Under no circumstances put your ammo with your rifle, they come utterly unglued about that. My last trip they made me take my ammo from my suitcase (AC) and forced me to send it as a separate bag which they then charged me $300.00 for, oh ya and BA will charge you 50 British pounds just to handle your firearm IF they deem you worthy of using their airline with a rifle.
Do you have your SAP 520 form for entry into SA?
You may not travel with more than 5Kgs of ammo, and this includes the weight of the enclosure which I found out after a rather long, heated discussion.........they're still wrong but you can't convince them of it. My argument was that their own regs very specifically say 5 Kgs of AMMO, it does not say an enclosure containing ammo cannot weigh more than 5 Kgs......regardless make sure your ammo enclosure locks, does not weigh more than 5 Kgs and duct tape it closed, if they open it to inspect it demand they retape it as you had it.
You must stand your ground when dealing with the various people you will meet who may go out of their way to f**k up your hunt. If you are getting the run around, demand to speak to their superior, go to every check in 3 hours in advance, and have lots of room on your visa and have 1000 USD on your person. If you are taking a rifle which you once had registered before this nonsense was cancelled here, and you have retained your old registration, take it with your papers, it makes things go much smoother. Most countries and/or airlines do not believe there are still countries where ALL guns aren't registered, the Brits particularly, so if you have your old registration, by all means take it, it just makes life easier.
Be diplomatic but firm, and go to the appropriate sites, and learn the rules. They change almost monthly, so seriously, do your homework and know what you are talking about, and don't let anyone try to f**k you over. My last trip through SA they or Air Canada would not allow ammo to be in your clothing checked bag. Make certain that your outfitter is going to have someone there to meet you at Jo'burg, and if for any reason you have a flight change, make sure you have a number to alert your outfitter. If not and your permit is not there when you arrive they will seize your rifle. You should have a copy of your SAP 520 on you before you embark on this adventure so if their rep doesn't show up at the airport (and it does happen) you won't get your gun seized.
It is NOT easy travelling with firearms, and DO NOT listen to anyone who tells you it is, it can be, but my last 5 trips have not been and it wasn't because of a lack of due diligence on my part, it's because hunting has become exceptionally unpopular with the masses and many will go out of their way to make your transit as difficult as possible.
I'm not trying to scare you, just prepare you for what can and may happen and it has happened to me. I spent 3 hours in an interrogation room in Inchon Korea with 2 very large, well dressed Korean gentlemen working for their national police force, trying to explain why I was in Korea with a rifle, which is forbidden under Korean law. All my papers were in order, but even though they spoke perfect English, it took me 2 1/2 hrs to realize they didn't READ a word of English !!!! I will be more astute next time.
Make absolutely certain that your rifle and ammo has made any airline changes and connections that you have to do. Demand at the check in that they confirm with their baggage handlers that your cases have in fact, been loaded into your airplane and get their names and write them down as having confirmed it. They won't like it, but it is your right and when you take names and write them down it is amazing how things seem to work out for the best...........someone with a name is now responsible...........it works!!! Plausible deniability goes out the window and you can name names and point fingers and they know it.
Lastly you absolutely MUST personally contact all airlines you will be travelling on, with a rifle, I said it before and it is crucial, they will inform you of their rules and procedures and it will make the whole experience a lot smoother. They also put notes with your reservation so everyone is aware and there should be no surprises. Being prepared and informed is your best possible advantage when travelling with firearms.