Up to 5-20% Strength based on the charge time of your heavy attacks. Stacks 3 times.
Hitting an enemy gives them 1-4 stacks of 2.5% Brittleness. Debuff lasts for 5 seconds and can have a maximum of 16 stacks.
3.5-5% Critical Chance for every 10% of magazine spent during continuous fire. Stacks 5 times.
10% Critical Chance for every 0.2-0.35 second while aiming. Stacks 10 times. Discharges all stacks upon firing.