Good luck! Looked at doing that hunt last year in Kyrgyzstan but got into my desert sheep,and then An antelope hunt, then, a group guys pheasant hunt, and my typical whitetail deer spend...so tapped my time and money out...
I would not be afraid of using the Berger..I have killed a crap load of stuff with a Berger 115, and 140 gain bullet, and stuff always was dead on the other end. I will say that bullet performance if based on retained weight is not confidence inspiring. Bullet failures happen and I'm bound to get burned one of these days. I don't use Hornady DGx bullets because they broke up and dang near lost a very expensive eland for me. If I were you and had a good load with a accubond, or a Barnes LRX bullet...I'd probably lean that way. If I hAd it dialed in with a Berger and practiced--I would not try to reinvent the wheel and put the bullet in the right spot. There is a lot to be said about confidence between the ears! It helps on an international hunt! Long trip, different time zones, language Barrier ..last thing you want to worry about is hey is my gun really on??? Have fun...it's on my bucket list...