Waited a while to post.
I agree with post 17. Tell soldiers they can keep what they capture, and for a handful of them, finding an enemy combatant who's carrying the desired item--then finding a way to justify engaging him--quickly supersedes the real mission. Commanders can't afford that sort of disturbance in the force, in you catch my meaning.
It comes to this: When a soldier writes something as part of his job, that writing is not his. He cannot copyright it, nor can he profit from it. His effort produced it; his understanding of the topic made it possible. But he did it for Uncle Sam, in Uncle Sam's employ. Uncle Sam owns it.
If a soldier manages to disarm an enemy--capture his firearm--he has done so because that's his job. His claim on that captured weapon is the same as the other soldier's claim on that piece of writing: Zero.
As for U.S. firearms that are leaving the inventory, all citizens should have an equal claim on them through legitimate sales (albeit in a somewhat demilitarized state). I see no reason for veterans to have dibs.
Yes, I am a veteran. No, I don't posses any of the firearms or other durable equipment that were issued to me over 27 years of service. They were mine to care for and use, not to own.