Will downsize implants by 50cc make a difference in projection?

It seems that you are moving too quickly in your decision.   I don’t think 50 cc will make much difference but there’s no medical reason to stop you from switching sizes. 

Dear anon604,
breast implant type and sizing selection is a complicated process and requires a detailed consultation that includes a discussion of your goals, a detailed examination, and a lengthy discussion. But the decision will always start and end with the patient. When it comes to sizing, we have all of our patients find 3 photos of their desired breast size. We ask for naked breast photos because clothing can obscure the true size (push up bras). Next, we consult with patients and go over the photos and take detailed breast measurements during a physical exam. Next, we using a sizing algorithm to determine a range of implants that will work based on the exam and the measurements.Lastly, during the operation, we use silicone sizers in the operating room to see how the size actually looks in the breast. We sit the patient up in the operating room, while asleep of course, and compare the sizer result with their desired look photos. If it is too small, we start the process over with a slightly larger implant. We don't stop until we get the perfect match.Of all of my breast augmentation patients, every one of them has been happy with their size due to this detailed and meticulous process. You don't want to invest time and money into a result that is either too big or too small.You should discuss your concerns with a board-certified plastic surgeon and make sure that your surgeon understands your goals.
Daniel Barrett, MD

You might want to also go down in height as well as volume. The more cohesive gel can feel a little firmer, especially with women with little breast tissue.  However, you need to give yourself time to heal first and let wall the swelling subside. Please wait at least 6 months before considering a change. You may find you are good.

Thank you for your question.  Usually a 50 cc difference in size will not make that much of a difference in volume but if you aren't happy with your current projection also then you could change the profile and size of your implants.  I would show your PS the look you wish to achieve and he/she should be able to select the right size and shape to get you closer to that look.  Best of luck to you.

There are many factors, besides breast implant volume that may come into play when it comes to the aesthetic outcome (including projection) achieved with breast augmentation as well as revisionary   breast augmentation surgery. For example, the profile of breast implant utilized,  degree of cohesively  of the breast implant utilized, adjustment of surrounding capsules if necessary… may be factors to consider in some cases. My best advice: communicate your concerns/goals carefully with your plastic surgeon. In our practice, I ask patient to communicate these goals with the help of goal photographs. Make sure that you are both on the same page prior to proceeding. Best wishes.