A trigger mechanism guard assembly includes two arms, each having a first end with a trigger guarding surface and a second end and a housing with substantially parallel side surfaces configured to at least partially enclose the second ends of the arms. The housing is configured to be movable relative to the arms such that the housing has a first position and a second position, the second position being closer to the first ends of the arms compared to the first position. Movement of the housing from the first position to the second position causes movement of the first ends of the arms away from each other.