Reasoning about actual causes of an observed effect is fundamental to many applications. Batusov and Soutchanski (2018) recently presented a first-order logic approach to compute actual causes. Built on a formal theory of action and change, namely the situation calculus, their approach is quite expressive, as it can be used to determine the causes of quantified effects. However, their approach does not find causes from a counterfactual perspective, nor does it link with the regularity approach to causation. This paper proposes a new analysis of actual achievement causes in the situation calculus. We study the natural properties that are necessary for actual causes and conditions that are sufficient for the achievement of an observed (possibly quantified) effect. We identify a property that is both necessary and sufficient for actual achievement causes. This is one of our main contributions. Our discussion leads to a new definition of actual achievement causes that includes the root cause together with a chain of relevant events. We show when our definition is closely related to the recent one proposed by Batusov and Soutchanski (2018).