never really though about this.
strangle enough i have a couple pairs, but its due to my dad.
when one of us buys a pistol if the other likes it we usually end up picking one up as well because we dont live near each other.
what has been happening over the years is my dad will flog off pistols he dosnt use to me.... which now that you have brought it up means i have a couple pairs of pistols.
smith and wesson 422/622 (one is silver one is black)
norinco 1911 2-tone x2
herbet schmidt 22 6 shootersx2
so nothing horribly fancy.
when my dad gives up his gun collection and i get it i will have a LOT of doubles now that i think about it.
Ruger 22/45 Lite, Browning Buckmark, Ruger Single 6 (mine is stainless his is blued), Kimber 1911, Sam Tactical Commander, Smith and Wesson M&P 9mm and i think he has a 45 as well so that will be a double, then a bunch of rifles.... 5 that i can think off right off the top of my head and at least 2 shotguns, wait, 3 shotguns.
so ya, i can blame all those doubles on my dad!