Posted this on another forum and the consensus was that this was either a modified 17 or a 18 which is f/a according to several viewers. Also, they said that with a few slide modifications and a back plate, you could order the parts fairly easily and have an unregistered f/a. Don't think i would would want to do that.
Still an interesting video. I would hate to " feed" that pistol.
If this link will not take you to the video, you can copy and paste. Hope it will work
Fixed the video link to show here...Shadow
One difference between a Modified, FA G17 and the G18 is that the G18 is Select Fire
Note the Selector on the rear of the Slide
(http://img3.wikia.nocookie.net/__cb20120301234618/deadliestfiction/images/5/55/Glock18c_01-1-.jpg)