How many guns are in America?

[Straw Man]

17. Interesting.

Some Kentucky permit holders are subject to monthly background checks.

North Carolina conducted checks for a large group of existing permit holders in March 2014.

In California, a technical issue caused NICS queries to be submitted multiple times in March 2015.

http://www.governing.com/gov-data/gun-background-checks-by-state-nics-chart.html

That would certainly skew the KY and NC results. I was not aware that state agencies could do this. An accurate number should still be possible to determine by computing the number of permit holders and number of months they have held their permits.

The NC data is too vague to yield a procedure. As for CA, though, multiple submissions should not lead to multiple approvals/denials. The latter data should be accurate.

Background checks are also required when owners pawn their weapons.

For all practical tabulation purposes, this is equivalent to a "sale" -- a firearms that was on the shelf goes back into circulation.

In any case, given the number of firearms that were out there pre-NICS, it would be impossible to come up with any reasonable estimate short of doing a "gun census," and we all know how wildly inaccurate that would be.