My good friend over Traction Control posted up the 2010 NICS check numbers here:
Just a quick check of the relevant numbers leaves a rather significant implication in ones mind...
There were approximately 14 million approved NICS checks in the U.S. last year (There were about 14 million checks, over 99% of which were proceeds or proceed after delay. less than 1% of NICS checks are denied... actually in most years it's less than .1 percent).
There are approximately 280 million non-prohibited persons over the age of 18 in the United States.
In most states, CCW holders are not required to go through a NICS check. There are at least 2 million of those in the U.S.
Each NICS check can include multiple firearms. There are no good numbers as to the average number of guns sold per transaction, various sources place it somewhere between 1.05 and 1.1... but obviously, it is a number greater than 1(discounting the very small number of checks that involve no firearm being sold, or people claiming their guns from pawn etc...)
That means the absolute minimum number of firearms sold in the U.S. last year is a little more than 14 million; or approximately one out of every 20 people over 18.
Oh and that's almost exactly the same number of guns sold in the U.S. in 2009; again, one for every 20 people over 18.
In fact, in the entire history of the NICS system there have never been less than 8 million approved transactions in a full year.
We can't really estimate how many of those are used guns, vs. new guns; because the firearms industry doesn't report on new gross unit sales, so it doesn't necessarily mean that there are 14 million NEW guns (and of course, no-one knows anything about private sales... But I'd guess it's somewhere around half and half new and used).
...and guns dont expire, go bad, or in general wear out.
Oh and there were 14 billion rounds of ammunition sold in the U.S. last year, to go with those 14 million guns.
Those gun owners who admit to pollsters that they own guns, average 4.4 guns per.
Lets assume that there is a useful life for a gun of 50 years... It's certainly much more than that, but let's set that arbitrary limit.
Somehow, I think the often bandied about number of 240 million guns for 80 million gun owners, is a bit low... I think it's an absolute minimum of about 400 million, and 100 million.