you should prestige.
anyway, for hardcore i would use this
M1A1 Carbine, or SVT-40 if you're lower than 65 - flash hider
bomb squad
camoflauge
(your choice here, not martyrdom)
for normal modes, i like these rifles
Gewehr-43 or SGT-44 - arpeture sight
bandolier
stopping power
second chance
or this submachine gun kit
thompson - extra ammo clip
bomb squad
stopping power
steady aim
and this russian overkill class kicks.
PPSh-41(extra ammo clip) and the PTRS-41(no attachment)
(your choice of perk 1, i suggest bomb squad or bandolier)
overkill
(your choice here, i use steady aim for the PPSh, or iron lungs for the rifle)