we (both Americans and Canadians) have some excellent .338 rounds and rifles that bring down grizzlies at 500 yards.

I have nothing against our forces getting the best available, however...
Exactly why do we need to buy a weapon system from another country ?

The 338 Ultra, A poor man's Lapua: Check out any hunting magazine or American Rifleman's latest. The Lapua requires lots of modification to work in a Remington action and that means high cost. The Ultra round is a factory available chambering and requires no modification to the Remington. These can be built for almost the same cost as a .308 sniper rifle.

The British Army says:
http://home.swipnet.se/longrange/british_army_338.htm

“It had to convince us that it had a 70 per cent chance of hitting the frontal aspect of a Land Rover at 1,500m – that’s seven out of ten shots on target – and it will. And there’s enough energy in the round to do disabling damage at that range.”
I have to admit, I have never shot a Land Rover at 1,500 meters

Sorry, but smells of politics to me