The in-game description even flat-out states that this weapon is “built around an assault rifle receiver.”
Why use the Riveter in MW3?
Stock: DAV15 Light Tactical Stock
We like a good stock to lighten the load.

Best Riveter class setup: Secondary weapon
Renetti.
TheRenettimakes for a great secondary pistol thanks to its burst capabilities and excellent performance at mid-to-long range encounters.
To keep you safe from any stray grenades as you sprint across the map, wear theEOD Padding.

Finally, theMunitions Boxwill complement our ammo-rich loadout to ensure that we aren’t left with an empty shotgun.
Best Riveter alternatives in Modern Warfare 3
Lockwood 300 or MCW.
That concludes our look at the Riveter.
For an in-depth ranking of Modern Warfare 3’s shotguns, see our guide to thebest shotguns in MW3.