@Sudsy,
Let me mount my soap box once again.
Most of the questions could be answered here by first using a Vernier caliper. Inexpensive digital calipers that measure inside, outside, and depth with acceptable accuracy cost about $20 and is one piece of measuring equipment we all should have in our tool box.
Measure the land to land diameter of the bore and the groove to groove diameter. The base bands should be just under the diameter of the land to land bore measurement. The top band should measure the groove to groove measurement. What are the measurements of your rifle and maxi-ball?
What you may have is a T/C barrel that is on the minimum tolerance for their barrels. Your mold may be on the maximum tolerance limits for the molds.