Puzzling.
IF....
You have been putting the radiator cap on FULLY, and it still pushes coolant to the overflow tank, that would indicate pressure beyond the caps rates 17 lbs, or a failed cap.
Where did your original tank fail?
and, was the failure caused by excessive pressure?
I would perform a pressure test in order to rule out or determine if something else might be going on.
Keep up posting your findings.
Marty