> someone posted it here on hn but i think it's been removed (by the mods, i imagine) since.

The submission: https://news.ycombinator.com/item?id=47425297 "Tech hobbyist makes shoulder-mounted guided missile prototype with $96 in parts" - https://github.com/novatic14/MANPADS-System-Launcher-and-Roc...

Seems to have almost as many comments as points, so guessing it got pushed down the frontpage list because of the "anti-flame-war" thingy HN has.