RF Online has a range of attack bonuses linked to different ammo types, please note that these boosts do not show in the gen-attack screen, below is the list:

35% Attack bonus

• Ceramic advanced beam cell

30% Attack bonus

• Ceramic exploding vulcan ammo

25% Attack bonus

• Advanced beam cell
• Energy magazine

15% Attack bonus

• Vulcan

As you can see, these bonuses do not cover all weapons.