The 140 Partitions work fine on game too--as do 160's.
The reason I tried the 150's was that 140-grain Partitions didn't shoot very well in my rifle. 160-grain Partitions shot OK, but it shot 139-grain Hornady Interlock Spire Points noticeably better. I was talking to Chub Eastman one day, who worked for Nosler at the time, who was an old .280 fan. He pointed out there was another Partition between the 140 and 160-grainers, and he'd found many .280's shoot 150 better than the other weights. So I tried the 150's and they shot so well I decided to just use them for everything, which worked great.
If the 140's or 160's had shot as well I'd have been equally happy using either one. I did take several animals with the 139 Hornadys, including my first caribou, and per usual they worked great, but I like Partitions a little more on really big game, and since the 150's shot so well I kept things simple and used them exclusively after finding they shot so well.
