A M4A1 with SOPMOD package, including Rail Interface System and Trijicon 4x ACOG. The barrel length is 14.5 inches.
US Navy
2003
<a rel="nofollow" class="external free" href="http://www.dtic.mil/ndia/2003smallarms/john.ppt">http://www.dtic.mil/ndia/2003smallarms/john.ppt</a>