Guns.com looked at numbers from NICS check and with 27.4 million checks, it is very likely the best selling year. Of course some checks are not sales related, but with increasing number of checks, it is reasonable to assume the number of sales increase as well.
Here is the full article
http://www.guns.com/2017/04/05/how-2016-became-the-biggest-year-for-background-checks-gun-sales/
From: Guns.com
