The Ultra Lightweight Mark V is a VERY nice hunting rifle. My .240 weighs 6 pounds 11 ounces with a 6x36 Leupold in Talley Lightweight rings, aqnd shoots very well with either handloads or factory. I haven't had any issues with the recent brass, and loads are very easily developed. The big game load I'm using now shoots into 3/4" or less with the 90-grain Nosler E-Tip at 3400+.

That said, I have two .25-06's and would suggest that it's more practical--and also available in the Weatherby Ultra Lightweight. It is pretty close to the .270, but with a wider selection of varmint bullets on the low end. Brass is of course cheaper and more widely available.

Years ago some gun writer mentioned running .25-06 brass into a .240 die, and having the case come out perfectly, right down to the belt. I tried it and the reformed case looked perfect, but wouldn't chamber in my Ultra Lightweight, even though the reforming was done on a Redding Ultra Mag press.

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