The gun that Chris used in Iraq was his own personal weapon, it was against regs to do that but my friend Monty built it identical to the one issued him. So unless they ran the serial numbers they wouldn't know the difference and no one ever did.
I will say, SOF guys are a unique breed, when a friend said he was sending a former navy SEAL over to go over a job and have me do some design and programming for his business I was skeptical, Stolen Valor being as popular as it is now.
Nicest guy you could ever ask to meet, and turns out he was certainly the real deal. I'll plug his business, CenturianArms.com, if you ever need quality rails, accessories or even a complete hand made rifle, you won't do better than dealing with him.