Many gun enthusiasts complain how amateurs believe that they know about firearms due to playing videogames like Modern Warfare 2, which feature real guns.

The owner of the gun site, The Firearm Blog, was surprised to realize that the most popular search term that led to his site was an obscure gun unknown outside the firearm industry, the Bushmaster ACR. That was until he realized that the gun was featured in Modern Warfare 2.

"I was surprised because, compared to the AKs, M4s and Glocks of the world, the ACR is relatively unknown outside of the industry," the blog's owner, Steve, wrote on December 8th, 2009. "Have any other bloggers noticed the Call of Duty effect?"

There follows a stream of anecdotes from gun enthusiasts about how videogames have turned gamers into "gun experts."

"I was riding around with a friend of mine when I asked him to stop in at this new gun shop," said one commenter, Robert. "He knows next to nothing about guns so I was surprised when he asked, 'Can you buy an ACR in there?' After explaining they don't sell it to regular people I asked him where the hell he had heard of it ... should've known before asking. He's an avid gamer."

Another funny story is told by Jim:

I wouldn't call it the Call of Duty effect as much as the Halo effect. He came in to a Pawn Shop I was shopping around at and asked for an "Ess Em Gee" (Submachine gun). The owner said that he didn't carry them. He then asked if he had any sniper rifles. The owner showed him a .270 (I believe). As the punk (hat cocked off to the side and his pants at a level where a belt would not allow them to fall) looked down the scope, he asked how to "zoom it" (a common feature of scoped rifles in video games). The owner showed him how to magnify and clarify the image. The punk said that he was just used to the rifle doing that for him. Finally the owner asked what the kid was looking for to which he replied "I just want to headshot some noobs! Like in Halo!" The conversation quickly degraded from that moment and ended very shortly.

Source: Firearm Blog