i think a lot of people get ama rules and actual law confused. plus this is a multinational forum of people so blanket statements like that are a little confusing.
Here's the issue that's getting confused - in absence of having a Part 107 license (which is REQUIRED if you are NOT part of a community based organization such as the AMA) you would fall under needing to be a member of a community based organization, such as the AMA (which, currently, is the only nationally recognized community based organization) and thus be covered under section 336. If you fall under section 336, you fall under the AMA's safety rules and regulations. If you do not, then you fall under the FAA's Part 107 rules and regulations.
I've not looked into the FAA's rulings, but I'm pretty sure the firing of projectiles from a UAS, whether lethal or not, is a no-no. Even if it isn't, that's a huge risk you'll be taking in a very politically charged arena with drones, spying, and guns. Under section 336, firing projectiles is a no-no, because you're falling under the AMA's rules. This is why some people don't like the AMA and what they feel is restrictive. I get it; I'm not going to argue that. But, if you don't have a Part 107 license, and you are expecting to be held under the Section 336 rules if law enforcement comes down on you, it's what the AMA's rules are that you have to participate under.
And from what I understand, if you are Part 107 and going under that ruling, you must carry separate insurance for your UAS - which, from what I heard at AMA Expo West, it was rather expensive.
Ultimately, what I'll say is this:
Fly safe, don't fly stupid, don't try to rock the boat and do something potentially dangerous (like taking pictures of incoming planes from the flight path at La Guardia or Chicago O'Hare airport, or following a military BlackHawk helicopter 2.5 mi. off the coast into restricted military airspace). If you fly smart, you fly safely, you'll have nothing to worry about.
Shoot, I had a sheriff come out to a baseball field where I was flying my drone at about 6:30 in the morning (I did it that early because there was NOBODY there - again, trying to be safe, so that I didn't have to worry about anyone running onto the field with my whirling blades on my quadcopter), and the sheriff asked me what I was doing. TECHNICALLY, I was somewhat illegal, as the baseball field is within 5 mi. of an airport, but I'm flying below the treetops and below the lights for the field with my drone - if a plane is flying low enough that they have to worry about the treetops and the light poles, my drone is going to be the least of their worries.
At any rate, the sheriff came out, asked what I was doing, and said, "Ok, cool. But if anyone shows up, please give way to them for safety's sake."
"Not a problem, sir. That's why I'm out here so early flying - no interference!"