No dupes for me...yet.
Krag 30-40, .30-06, 12 gauge, 20 gauge, and .22LR
I'm planning to buy an AK-47 next, so add 7.62x39 to the mix.
After that, I'm 99% sure I'm buying another .22LR, probably a Citadel M1 Carbine replica.
With the price of ammo going nuts, I'm betting that I'll be buying lots of .22LR guns over the next few years.