Quoted By:
So here's a fun artifact of gun control. George Bush Sr. banned the importation of 'assault weapons' in 1989, in the law was a number of features which were listed for semi-automatic rifles, pistolgrips separate from stocks, folding stocks, threaded muzzles, flash hiders, grenade launchers (as in the muzzle kind), bayonet lugs, barrel shrouds, and detachable magazines. If it had two or more of these features, it could not be imported.
Naturally this meant that people just changed existing rifles so they could be imported; take an AKM, G3, or FAL, remove the bayonet lug, replace the flash hider with a permanently fixed muzzlebrake or just leave it bare, and replace the pistolgrip and stock with a 'thumbhole' stock, which in a sense meant that the stock extended down somehow and formed a loop at the bottom of the pistolgrip, the definition of a thumbhole stock wasn't particularly strict.
Here is the Steyr USR; Universal Sporting Rifle, it's outright a semi-auto only Steyr AUGA2 with no muzzle device, and with a flimsy flap behind the pistolgrip which fulfills the legal requirement to make it not a pistolgrip.
The thing here is that this was only a ban on *importation*, meaning once these were in the US, you could put on whatever grip and stock you wanted, put on whatever muzzle device you felt like, add a bayonet lug somehow, etc, so that's not uncommon.
You could buy this USR back then and just grind and polish away this flap, then have the muzzle threaded for a device of your choice, and this was all good.
