(adsbygoogle = window.adsbygoogle || []).push({}); Below you can find all my weapon rates for black ops 3 weapons. Not used every weapon yet but based on the information rough list. Some tier 3 weapons are not bad but have nice niche. Apart from the KRM which is terrible. [Trust me you don't want to touch it]

Subject of attachments find iron sights being the best choice for most weapons.
High Cailber works on burst weapons
Grip only useful for certain guns
Stock is okay for ARs find myself using it the most with quickdraw being another good choice.
Can see fast mags being useful for SMGs
Laser works best on SMGs

Don't need attachments most guns naked work fine even shotguns and long barrel changes your overall range in a bad way.

Assault rifles

Tier 1: Man of war, M8A7

Tier 2: HVK, ICR-I

Tier 3: Sheiva

HVK is the best average gun in the game expect to see most people running it in public lobbies. Can't go wrong with most weapons apart from the Sheiva.

Sub machine gun

Tier 1: VMP, Pharo

Tier 2 Kuda, Vesper, Razorback

Tier 3 Weevil

Expect to see most players again using average guns Kuda, Razorback with some VMP. Only weapon I dislike is the Weevil but does have that 50 clip.

Light machine guns

Tier 1 48 Dredge

Tier 2 BRM, Dingo

Tier 3 Gorgan

Expect to see most players running the BRM or Dingo

Shotguns

Tier 1

Tier 2 Haymaker, Argus

Tier 3 Brecci

Tier 4 KRM

KRM is just bad avoid it simple as that, wasted too much time on that gun trying to gold it given up.