There are not many sheep (worth hunting that is) in Australia, but I do have a mountain rifle that would fit the bill. Being a bit if a traditionalist (and when I was getting into hunting with the writings of the late, great Jack O'Connor) my current rig is:
> Winchester pre 64 Model 70 Featherweight
> Caliber = .270 Win
> Leupold VX-I 4-12 x 40
> Conetrol Custum 2 bases and projectionless rings
> Load = 140 gr Hornady SPBT interlocks at a chronographed 3,044 fps. This is a warm (over table maximum) for alpine hunting conditions)
Total weight a tad over 7.5 lbs (not an untra alight) but light enough to attach to a backpack (see pic below)
Though I have not done any sheep hunting I took a Tahr and Chamois hunt in the southern mountain of New Zealand last winter with this rifle. For this hunt my guide, Croc Adams at Tahr, Stag, Chamois and Fallow Deer hunting in New Zealand's South Island
suggested a 200 yard zero with gave a PBR of 250 yards.
I took this representative Chamois high in the snow (around 4,500 feet elevation) from above at around 200 yards. Clean one shot kill.
However, for a sheep hunt (after reading the experiences on LRH) I'd opt for O'Connor's 3" high at 100 yards (close to 275 yard zero) putting it 1.5" low at 300 yards and 12.5" low at 400 yards.
However, if I were buying a sheep/mountain rifle today I think I'd break with tradition and it'd look something like this:
> HS Precision PHL (I like the ½ MOA guarantee), Kimber Montana or custom build on a Winchester classic action (current fwts and EW are, in my view, too heavy for a mountain rifle)
> Caliber = 270 WSM
> Leupold VX-3 3.5-10 x 40 CDS
> Conetrol Custum 2 piece bases and rings
> Load = 140 Hornady SPBT interlocks at around 3,200 fps
This is a great thread and enjoyed immensely reading the views and experiences of the posters.
Cheers and God bless,