Everybody knows on this business, that armament dealing goes undercover on toys...what's the question here...the same way you can't print money bills on any printer...and I mean..all printers...(of course, I saw the modification of the file, to get a print...but..the size problem remained) the same way, all 3D printers have disable all gun parts design...they are not that stupid..or some of their maids...aren't...so its really easy to find armament dealers...

https://www.cgtrader.com/3d-models/military/gun/the-m72-law-light-anti-tank-weapon-rigged-animated-with-sound