In this country I don't think it is. I say that based on ammo availability. I have yet to see a box of .338 Lapua ammo anywhere, while .338-378 Weatherby is available at most any well stocked gun shop. The .338 Lapua is more popular overseas. The British use it as a sniper rifle platform in their Accuracy International long range rifles. I don't see the belt as a plus or a minus. American Magnum rifle cartridges have been, and still are, belted. Now it has become all the rage to go "belt less". I like tradition and belts on Magnum's. Bill T.