SenorBeef- Agreed on all points. Call it a lack of explanation, not lack of knowledge. 
By “precursor” I meant in terms of a weapon in the caliber, adopted and issued prior to the Barrett, not that the Barrett was developed from the M2 or designed to replace it.
As for the Russian heavy, I knew they had something in that ballpark, but I don’t know any specifics.
Mangeorge- Again, why is that number so hard to believe? If we printed out the United States Tax Code, it would result in pallets of paperwork weighing literally several metric tons.
When I looked up my local vehicle ordinances, the Library had about twelve feet of books concerning just civilian non-commercial vehicle regulations.
All those regs I mentioned before were just off the top of my head. I have no idea how many I’m not even aware of- The crossing state lines bit above, is a good example… In some places you can’t bring a firearm within a thousand feet of certain buildings, like schools. So driving by with it locked in the trunk and unloaded, is a crime- and another law.
To be perfectly honest, I’m surprised it’s “only” 20K, a number I’ve heard bandied about for a decade or more. Admittedly, making it somewhat more likely it’s an urban legend. The point, I suppose, is that we have thousands of laws already on the books. The DC shooter is, for example, already breaking innumerable laws, not the least of which is murder and attempted murder.
And yet, if or when he’s caught and his weapon identified, the hue and cry will arise to ban whatever class of weapon it is/was.
Murder is already illegal, regardless of means. Current laws and the threat of prison and possible execution don’t seem to be deterring the DC loon, so why does anyoone think yet another law will be any different?
