Sounds like you are degrading the image with your workflow. I doubt the necessity of Fractals to achieve a 13x19 from your captures. Recapping some of the points above and inserting a bit of my own workflow.
1.After importing the RAW file into Photoshop save as a .psd, "not .jpg". Every time you edit and save a jpg there is a resultant compression loss and it will show up on a 13x19. If you need to do further editing to your RAW file, make a "Duplicate" image, and perform the edits on the Duplicate. Essentially your RAW import is your negative, save it untouched, and the Duplicate of your RAW is your working negative, save it also. imagename_raw, imagename_working.
2. After you have made the necessary edits on the RAW file Duplicate, make a "Duplicate" image for "each" crop size required, and crop. As mentioned above, I put the image size in the file name to avoid confusion, imagename_5x7.psd, imagename_13x19.psd.
3. Anything from 240 to 300 DPI will print, I use 288 DPI as my working resolution.
4. I save files in sub-folders within a job name folder. I title the subfolders: Original, Edit, Print. orig_filename.psd, edit_filename_57.psd, print_filename_1319.psd, etc.
To recap pertinent points, save as .psd, and get into the habit of working on duplicate images. I am not suggesting you have to save a whole bunch of files permanently, but it does come in handy if you need to revisit the file at a future date for another print, or re-edit with new found knowledge. best...skip