As future tense, yes, it is common and natural. There are 3 types of Korean ending style, formal polite style, informal polite style and informal plain style, and they are used with different level of people and in different situations. What you asked is an informal plain style and you can use it between close friends or close younger person. Formal polite style is "잘 것입니다", and informal polite style is "잘 거예요."

잔다 잘거야 자야 겠어. 자다=잠자다 잠잔다. 잠잘거야 잠자야 겠어.