If you are sure that there are no leaks then we need to pump the brakes numerous times with the engine running. Do the brake actually hold or does the pedal get a little stiffer? If it does, then you most likely still have air in the system.
If when you step on the brakes and it goes to the floor and the brakes are NOT applied, meaning you can spin the wheels with your hand while the brake is depressed, then your master cylinder is not sending brake fluid to the calipers or wheel cylinders. However, if you replaced this and the booster then it sounds like you still have air in the system. Especially the fact that all you did was change the calipers and the system was working prior.
Let me know if I missed something but I would suggest you put another bottle through the system and see if you can get any more air out.
Monday, May 13th, 2019 AT 6:07 PM