spat
.700 Nitro Express
I have serious guns, and fun guns.First, why don't you have a profile picture? Looks weird, one blank color.
I am a fan of the Keep it simple. I do not like to tie my inventory up with a bunch of different calibers. A few different ones is all I need.
For serious guns I try to stick to the most common military calibers. 9mm' 5.56, .308, etc.
I have a few serious guns in others as well, .22lr because of course. Serious doesn't necessarily mean 2 legged critters. Being able to put some rabbit on the table can be important in a SHTF situation too.
.380 because they carry *so* easily.
5.7x28 because I really really like the PS90
But, I've also got some just for fun stuff too.