I switched to the 168 vld in 2008, shooting a Tikka 7mm, since then I've shot a mountain goat, full curl big horn, black bear, 2 six point bull elk, 6 cow elk, multiple antelope and deer and have never lost one! One bull was at 520yrds 2 shots, the other bull was 465, one shot. The only animal I wouldn't use it on again is a buffalo, watched my boy put 6 into the chest of that 1600lb beast! (would use a more solid bullet for that). Big horn was a 280yd shot quartering away and DRT! I did some testing today and that bullet put out the best results out of my Cooper on paper, I shot the 175 Nosler LRAB, Hornady 162 & 175 eld-x, Berger 168 & 180 vld's and the 180 hybrid. But first and foremost you need to find the bullet YOUR gun likes! Pretty much every one of those bullets will have no problem killing a big horn out to 500 yrds!