I can only speak to the idea of C competitors, but at the World Shoot, the U.K. always has a team, as does Northern Ireland.
We have a gentleman from the U.K. who comes to Canada to shoot, and he has explained their laws. The handgun ban isn't complete in the U.K. The Channel Islands and Isle of Man both allow handgun ownership, as does Northern Ireland. The people in our sport who want to participate travel to those locations, train and compete there, and then compete on the world stage.