05-27-2012, 06:48 PM
IIRC, the .338 MMG mechanism is derived from that of the XM307. Although it doesn't really answer the question, there is a closeup of the XM307 bolt operation at 1:37-1:42 in the video below.
http://www.youtube.com/watch?v=owZ4Hq8y_rs
http://www.youtube.com/watch?v=owZ4Hq8y_rs
