The British have painted themselves into a corner for the traditional approach to establishing a monarch. Anyone pulling a sword out of a stone would be thrown in the dock for violating British knife laws. And trying to update that to pulling a SA80A3 from a stone would violate British gun laws. If they used, say, a Nerf mortar, the Lady of the Lake would be laughing so hard, it would ruin the monarchical succession ceremony. Aspiring royals could come to Texas and pull out whatever they want, up to a B61 at the Pantex plant, but that would, as Dennis the Peasant would say, be "no basis for a system of government" of the UK. So, yeah, this is a real monarchical crisis into which the Royal Family has gotten itself.