3D Printed Weaponry Now Functional

Another first for 3D printing: A pistol constructed from 3D printed parts has been successfully fired. 
 
The gun design was an AR-15, a "a lightweight, 5.56 mm, air-cooled, gas-operated, magazine-fed, semi-automatic rifle", according to Wikipedia. Gun enthusiast HaveBlue selected this configuration due to its small caliber and the uncertainty of whether the 3D printed parts would withstand any higher energies. The parts were printed on an older model Stratasys 3D printer in ABS plastic. 
 
We must tell you that the entire gun was not 3D printed. Instead, a key part called the "lower receiver" was 3D printed and installed with other traditional parts to make up the gun. While it's just a single part, the lower receiver houses the operating parts and evidently in the USA this part is legally defined as the "actual firearm" due to its mechanical importance. 
 
HaveBlue decided on performing the test and rigorously designed a lower receiver that would fit into AR-15 components. Once assembled, he took the experimental weapon out to farmland and after first testing the weapon with a conventional aluminum lower receiver: 
  
I switched out the lower for my printed version and double checked the operation.  Would it hold up?  Again, one round in the magazine, cock the gun, squeeze the trigger, and…  Wouldn’t you know it, I shot my eye out.  Just kidding – it functioned perfectly.  Testing again with 2 rounds, then 3 rounds, then a full magazine.  Everything ran just as it should, magazine after magazine.  To be honest, it was acting more reliably than a number of other .22 pistols I’ve shot.  I ran close to 100 rounds through the gun before getting annoyed with not actually being able to aim at anything, and decided to call the experiment an overwhelming success.
 
HaveBlue believes this could be the very first instance of someone successfully firing a 3D printed gun. 
 
Via HaveBlue (Hat tip to Marney)