Congratulations
Your 35X30-30 should be a dandy.
I have a 35 Bullberry which originally was a 375 Winchester case necked down to 35. I understand that cases can be made by necking up 30-30. Now days I use 38-55 cases from Starline as the parent case.
I have loaded some 180 XTP's for mine, but I have not shot anything with them so far. I always used 180 SSP, and still have several on hand for it.

Bob R