A lot of weapons in Infinite Warfare are based on actual weapons that exists in real life. This post is created if in case you need to add trivial info to dedicated wiki pages or to another site like IMFDB(Internet Movie Firearm Database). "Classic" weapons NOT included. This has been made out of my spare time and boredom, and should be taken with a grain of salt.
Anyway, here are some weapons based on my observations. Some of them are based on a weapon entirely, some of them are of original design with parts derived from real weapons, and some of them which I like to call "frankenguns(2+ guns mixed together)".
INFINITE WAREFARE WEAPON = REAL LIFE WEAPON
NV4= M4 carbine
KBAR 32= Tavor Assault Rifle
Type 2= FMG 9
Volk= AK assault rifle
FHR 40= Again, P90
Karma 45= Kriss Vector
RPR Evo= F2000
HVR= UMP 45
RAW= QBB 95, in non bullpup config, and belt-fed.
Titan= Ameli, MG3
KBS Longbow= Remington MSR, FNH Ballista
EBR 800= M14 EBR
Widowmaker= Cheytac Intervention
DMR 1= M1 Garand
Reaver= KSG and M1216 hybrid
Banshee= UTS 15
DCM 8= P90 (IW really loves the P90 design)
Rack 9= SPAS 12
EMC= M&P Shield(pistol grip) and Glock(slide) hybrid
Oni= honestly have no idea what it's based on.
Kendall 44= Glock
Hailstorm= Mateba autorevolver
Sorry(not sorry) for lack of visual aid, but there is a simple search to see the weapons yourself.