Jimmy,
A hole under the forend in the lower rib will not affect ringing, IMO.
jOe,
I believe you are right about a barrel with delaminated ribs still ringing. A good visual along with the ring test is needed. If the barrels don't ring, a problem is very likely. If they do ring well, a problem is less likely. Not an absolute test. But, it helps narrow it down.
Also, all 'rings' are not the same. What someone says is a good ring, may not be what another says is a good ring. I knOe that after re-laying the ribs on the Parker and leak checking the joints, the barrels rang like Big Ben. A short ring is an indicator. How short or long is subjective.
