500g
Are you familiar with Hollands 8 dram 10 paradox or the steel cored bullets? The bore diameter of the 10 is .805 really more of a 9. The bullets have been said to pentrate an elephant shoulder to shoulder.
I have not personally shot any elephant,yet, but I have an 8 bore gun that came with film of the previous owner using the gun in Africa in the 50's shooting elephant and a one shot stop of a charging rhino.
I don't advocate using a 3.5 to 4.5 dram 12 bore paradox on elephant but a friend just returning from Africa had an opportunity to shot a cull elephant and after it was down conducted penetration tests with a 12 paradox using bullets of 20to1. The results were surprising.