Weapon stats can be misleading sometimes in this game as they do not show you DPS (Damage per second) and only show you Damage, RPM and Mag size.
Damage reveals burst potential. RPM is how fast you fire.Mag size will determine how quickly you'll need to reload.
You may find addition stats on items which can affect gameplay, such as "Damage to Elites" where your weapon could be very affective against boss or named characters.. however fails to perform against regular targets.It also recommended that as a player you use different weapons with different ammo types so you do not have to resort to using your pistol (which has unlimited ammo) as this allows you to adapt to play styles.