3d Printers and gun manufacturing

Gun laws are a major controversy in America especially after  events like sand hook , the navy yard shooting and columbine. while guns have many Americans wondering what can be done gun makers and gun smiths make a lot of money off the fire arm and defense industry. but lately gun manufactures are rising concerns over the  value of  3d printing of firearms a technology which is currently being tested out and successfully tried. the method means a big head ache for ATF who may be soon cracking down on the manufacture of 3d printed firearms. currently AR-15  lower receivers have been made using CAD design and 3d printers. this could potentially make the manufacturer of fire arms at home a realistic and affordable solution to spending money on buying a expensive premade fire arm. while the guns may be subject to currant ATF laws it will certainly be harder to stop and or control home printed  lower receivers and weapons.