As 3D printers get more advanced, things like firearms, cars and even entire homes, can be made in 1-day or less. YouTube user “cozmogeek” spent a few months building a fully-functional AR-15, and fires it at clay pigeons on camera. “This was printed in ABS with .2mm layers on my Ultimaker 2. It uses $8-10 worth of filament, and unfortunately it took me 3 tries to get a good print. It also takes 24-48 hours to print depending on your settings. I’m sure I could get more good prints without so many failures now that I have figured out the process a little better. Supports are critical for this print since most of the part sits on supports,” said cozmogeek. Click here to view the first image in today’s viral picture gallery. Continue reading for the five most popular viral videos today, including one showing how to open a padlock without a key.