Aw, I thought this would be about real ones. IRL the 1911 has to be my favorite pistol. I like running around with it in BF3 as it is still a formidable weapon compared to all the automatic sidearms. The M1 Garand is also a beautiful rifle, although I've never held one. The only recent game I recall having it, since WWII shooters don't occur any more, are World at War and BF: BC2.
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FN Five Seven
Sig Sauer P226
H&K G36C (H&K in general really)
As much as it's overused in CoD, the Magpul ACR (Remington, Bushmaster?) is a really neat gun. I also really like seeing the M4A1 all kitted out with loads of attachments and modifications.
Of course you have to mention the Colt 1911 simply because it's the grandfather of the modern pistol design.