A rule of thumb for plated bullets is to use midrange loads if no loads are available for your particular bullet. So, find a load using a similar profile bullet as the Berry you're using and use that data.
I don't think the XTP load is one to use, since the XTP is a jacketed hollow point. They look similar from the side, but act differently.
Many people use lead bullet data when loading plated bullets to be safe. If you go to Berry's site, they say not to exceed 1200 fps with their bullets.
If you have access to a Lyman's reloading manual, there will lots of loads in there for lead bullets of many types.
Check out Hodgdon's web site. They have all sorts of loads available there. The load you mention is a max load per that site. The lower load is 6.1 grains of HS-6 for a 180 grain XTP.