One of my favorite repeat discussions.
The plane taking you to Africa is an INTERNATIONAL flight.
So, IATA guidelines matter. Not the local flight rules. Plenty of staff will be confused.
"amount of ammunition up to 5 kg."
For the individuals in the industry capable of reading help them out by bringing a printed copy along with you.
The policy guideline does not include the packaging in the weight.
The policy reference:
"Ammunition (cartridges for weapons), securely packaged (in Div. 1.4S, UN 0012 or
UN 0014 only), in quantities not exceeding 5 kg gross weight per person for that person's own use. Allowances for more than one person must not be combined into one or more packages. "
Securely packaged, it does not have to be in the original boxes. It can be in your checked (obviously) luggage.
Enjoy