Honestly hoppy, 20 minutes on YouTube and you will know more than that test shows. If you really want this to be a career I think you need to spend the time / money on a real armorers course, or perhaps even the gun you will hold yourself out to the world as an expert in.

Btw, Mr. Stoner designed the AR-7 survival rifle. It's a common mistake to confuse the two. What you are looking for is the Assualt Rifle - one five. I'm pretty sure that Forrest Gump designed it just before he was sent to Vietnam to kill Asians. Tough break that they would throw in a trick question like that on you.