A guide for centering transit ammunition rounds generally includes a plate having an ammunition round passage port therethrough along with a plurality of spaced apart ammunition round contact members disposed around a circumference of the passage port. A plurality of moveable arms is provided with each arm supporting a respective member and enabling radial movement of the respective member to and from a passage port center. Each arm engages an adjacent arm preventing non-equidistance spacing of the member from the passage port center and a plurality of biasing elements may be provided and disposed in positions urging a respective arm and member toward the passage port center.