Here is the gun part I saw on FB... A future soldier time travels into a gun store: "I need a rifle to kill aliens that are mostly bullet proof." Ok, you're probably going to want a larger caliber, probably .308, or for armor the added velocity of 6.5 Creed might... "No, we only have 5.56." Ok, no problem. You're going to at least want a longer barrel to keep as much velocity as you can. "I was thinking like, 7 inches." Ah, ok. If portability is a big concern you're probably going to want a super compact PDW style stock. "I need the longest, heaviest stock you can find." ...Ok. Lets talk optics then, a 7" 5.56 is gonna be pretty limited on range so a simple red dot... "I need magnification." Oh, are these aliens hard to identify? "They're gigantic." Oh. "I tell you what, go ahead and put a red dot at a 45. They look sick." Will you ever use it? "I will not." ....so, aliens huh? That sounds rough. "They have incredibly heightened senses. They can smell blood from a mile away." OH. Well, now the shorter barrel makes a little more sense. You're making room for a big suppressor. "A what?" A silencer. Especially if you're going to be shooting these in close proximity to other people, the concussive forces will be... "No thanks. We'll probably shoot a dozen of these full auto in a concrete stairwell." That's...I think you're making my point. "We'll also be fighting in dimly lit areas." You'll want a super bright weapon mounted light. "No I said they'll be dimly lit. What's your dimmest light?" How is this war going for you? "We're losing terribly."