DD/DDD with 300cc Removed - What Size Will I Be?

If only 300 cc's per side are removed than I still fee;l you will be a D cup. BUT you failed to post photos so very hard to guess the size or give accurate advise. 

Unfortunately, there is no direct correlation between the amount of tissue removed and the ultimate cup size that a patient will wear after breast reduction surgery.

Before undergoing the breast reduction procedure it is very important to communicate your size goals with your surgeon.  In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as “natural” or “C cup” or "fake looking" means different things to different people and therefore prove unhelpful.
Also, as you know, cup size varies depending on who makes the bra; therefore, discussing desired cup  size may also be inaccurate.

Best wishes.

Typically most insurance companies require a minimum of 500 gms per breast to be removed to trigger coverage. With the average cup ranging from 150-200 cc, it is probable that this will produce a 2 cup reduction in size. However, this is only an estimate