Retarded COD fanboys who think playing the game turns them into instant weapons experts (try reloading ammo and fixing guns like I have, then talk to me, kiddies)
Sadly, XBL does not allow me to post the transcript of the conversations, but I'll give my most memorable example (note: the gamer I talked to will be noted as 'Deluded_Dumbass', since I don't remember his gamertag):
Deluded_Dumbass (to another gamer): The recoil is stupid; a .50-cal doesn't jump around like that.
Me: The only stupid one is you; you were running around firing it from the hip, which is highly infeasible to do.
Deluded_Dumbass: What are you talking about, you fucking retard? A .50-cal doesn't weigh that much!
Me: You've gotta be kidding; unloaded, the rifle alone weighs over 28 pounds and if you tried hip-firing in real life, you'd either end up on your ass or have it fly back and kick you in the face, which you would deserve (Note to readers: This is the M107 mind you; the shorter versions - the M90 and M95, as examples - weigh a bit less). The only time it doesn't have as bad of recoil is when you're firing with the bipod unfolded in the PRONE position
Deluded_Dumbass: Whatever, bitch, you don't know what you're talkin' about *leaves lobby*
Me: *facepalm*