Free ranging Aoudad, Sweetwater Texas really!!! I spent a little time in Abilene (3.5 years) courtesy of Uncle Sam back in the early 60s. And all this time I thought the only wildlife around Sweetwater was rattlesnakes. I'm not very familiar with your 280 Remington but am assuming it is similar to a 7x 57 /275 Rigby on steroids. If that is correct you shouldn't have any trouble with African PG as long as you stick to heavier bullets like the 175 Gr. you mentioned. AH is certainly the best site to help you plan your safari. The thing you want to avoid most is surprises. Your chosen caliber is a little bit unusual, for that reason I'd check with your outfitter to see if it is available in Africa. I do know that in South Africa there is a small chain of retail stores called Safari and Outdoors. You can check their web-site for ammo availability. Good luck with your planning and hunt, if you have any questions just ask them.