There are a variety of factors and combinations thereof which could be causing your problems, but since the 25-06 chamber is TC's problem child, I'd first check the interior dimensions. A local had one of these a few weeks ago, and it was beyond SAAMI specs. But because he is an avid reloader, I showed him how to deal with the situation, and he's had no more problems and even took a nice deer last week.
Someone shooting factory loads, however, would not have those options, and if it is indeed an oversized chamber, a trip back to TC is in order so that they can send you a new barrel.
Can you do a cerrosafe cast?