Does anyone have one of these and how does it do with factory ammo? I got a box of 140 partitions but haven't had it out to the range yet.

I'm like you, got a new Sendero in 7mm Ultra Mag but haven't begun to work with it yet. Several of my friends use them and swear by them though. Two of my buddies took Mule Deer at long range this year using 140 Ballistic Tips and reported spectactular kills. In both cases the bullets had been placed behind the shoulder with little meat damaged. One used the 7mm Ultra and the other the 7mm STW. I'm thinking the Ultra may be the ultimate long range Mulie getter.