Specifically any ARs or SMG's that perform well in hardcore game modes. I tried the PDW but it was terrible at range. any AR's that kill in one hit? --- Not going next gen unless backwards compatibility is put in place
Peacekeeper shreds everything on hardcore, even at ridiculous ranges. Just be prepared for tons of idiots to toddler rush you for using a DLC weapon. If I'm not using the Peacekeeper, I tend to stick with the MSMC. Its iron sights and stability just work well for me.
Otherwise it's hardcore, so all the weapons are relatively effective. It's just a matter of what your playstyle is. The M27 is probably one of the easiest assault rifles to use for long range, and just in general really. The AN-94 is especially deadly if you have decent aim (especially on the first shot), but if your aim isn't very strong, be prepared to have a hard time hitting anything up close with it. The Type 25 is basically the opposite of the AN-94 - it'll annihilate anything at close to mid-range in hardcore because of its rate of fire, but you'll likely have a harder time hitting longer range targets with it. --- Hostis humani generis. http://thebrink.us/boards