The volume of a "shooter" can vary widely depending on the specific drink and the preferences of the person making it. However, shooters typically contain between 1 fluid ounce (30 milliliters) to 2 fluid ounces (60 milliliters) of liquid.
If we take the most common range into account, a shooter would typically contain between 1 fluid ounce to 2 fluid ounces, which is equivalent to approximately 28 to 56 milliliters.