Help me finish my zombie hunter collection!

[Soginator]

Well they aren't really rare guns, but I decided I would get a gun of every common caliber and jokingly call it my zombie hunting collection. So far I have
Handguns:
SA XD9 4in
Glock 22
SA 1911 mil spec
Ruger GP100

Shotgun:
Mossberg 500 tacticool

Rifles:
Ruger 10/22 takedown
Savage AXIS XP .308
DDM4v1
S&W M&P10
Arsenal AK47

Next up I was thinking of getting a .44 Desert Eagle and something for super long range. Was thinking of a .338, but I could use help deciding caliber and rifle. Also I was informed .380 might be considered common.
While I don't plan on upgrading the calibers I have with exception to the .45, if you have a good suggestion to trade up to I could always use opinions.

[dfens]

I'd think carefully on the .338 Lapua I thought about one for fun if I were to pass on a .308 until I saw the price the ammo goes for.

It's around $4.00-7.00 dollars a round so you'd better reload and or hand load that sucker or not shoot it that much.

Plus all the rifles I'd want in that caliber are wicked expensive. I could afford it but don't get out to long range shooting enough to justify the purchase to own one at this time.