What is the base chance of the Cryo Ammo power to freeze an enemy?

The Cryo Ammo power has a certain chance to freeze the enemies you shoot at, but the description of the power doesn't mention how high that chance actually is. The second rank of that power increases the chance to freeze an enemy by 30%, but 30% of what?

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How high is the base chance to freeze an enemy?


Depends on the fire rate of weapon, a sniper or shotgun will often freeze in a single hit, while automatic weapons often requite several rounds of fire.