Not during tourneys (speedball), at least not any event I have ever played in. You are allowed to have them in scenario though.
My advice to you and your team would be to come up with codes or at least specific names for each bunker and practice on this before or after a regular practice. Have half of your team or another team move around the field with no guns (either team) and try and keep up with where they are. Have the moving team "put you in a bunker " and then they move. When you come back out try and find where they moved to and the pass the word around to the rest of the team.