Wildcard Search in CF10

I create a collection by indexing a bunch of .pdf files and then I use CFSEARCH to search for a string in the filename.

In CF8 with Verity this was easy:

*searchterm*

In CF10, even if I don't use the leading * I cannot match any alphanumeric sequence.  For instance I want to search for M1234 in a filename that has M12345678 but Solr finds nothing.  If I get rid of the M and just search for 1234 it will find it.  Some of the strings however it makes a huge difference in the number of results returned.  I need to be able for the user to input an alphanumeric search term and CF return the results.  I'm finding this impossible.