5kgs is a lot of ammo. Unless maybe you are going on a high volume cull hunt I can’t see why someone can’t fit ammo and case onto 5 kg/11 lbs total so it’s a non issue. That generally gives me 80 rounds of 375 H&H or 300 win. I really can’t remember ever shooting more than 40 rounds on a safari.
This past trip was 40 days in Africa. I had to purchase 30-06 and was lucky to find Africa Outdoors had 2 boxes of 35 grain, Hornady 22 Hornet ammo. I purchase 3 boxes of Oryx 30-06 165 grain and 1 box of 25 count that I thought was 50 count, the same as I have purchased here in the US. The hunt was originally planned for 21 trophy animals, 1 cull cow buffalo and a friendly shooting contest. It turned out, TIA, I hunted more trophy animals and added: 4 cull impala, 1 cull blesbok, and we didn't have our friendly shooting contest.
My 3 gun battery was:
458WM with 50 rounds, all 500 grain bullets
30-06 with 50 rounds, all 165 grain SST bullets
22 Hornet with 50 rounds, all 55 grain bullets
I was just shy, about 1/2 to 3/4 pounds, of 5k or 11 lbs of ammo using my luggage scales and a Walmart bag. The ammo case with minimal amount of foam to secure my ammo weighed right at 1 1/2 pounds.
Agree on my previous trips with one and two gun battery, respectively; 5k/11lbs of ammo for 5 to 10 PG animals plus rifle/scope or other sight check is can bit much.