I have an early model Sendero in 7mm Rum, and the barrel has just about been used up. I'm trying to decide what chamber to put in a new barrel for this rig. With the magnum bolt face, that eliminates a lot of chamberings and directs my attention in a certain direction. I want this gun to be an accurate long range rifle for deer, but I'm not going to shoot past about 800 yards. I've already got 7mm RUM and 300 Win Mag dies, but buying a new set of dies won't deter me either. What do you gentlemen or ladies suggest that I do? Thanks for you input.