The load with the Hornady XTP and Unique powder should be a really light load ideal for target practice, But, I would not waste a bullet like the XTP on loads suitable for nothing more than paper punching. And as for your priming issue, I have never experienced anything like that, however, I use Hornady or RCBS shell holders and that combination has worked for me after priming several thousand 44 special/44 Magnum cases.