Unless you are loading low pressure "cat sneeze" loads using shotgun powder (unlikely in a caliber that small), or maybe blanks, you need to press out the primers and use the right ones. There are all kind of problems you can have with pistol primers in rifle cases, and some of them are really bad. If you are careful you can reuse the pistol primers to load practice ammo.
If you had primed pistol cases with small rifle primers, that is safe and can actually work (it can also cause misfires) and would be worth shooting a few and see how it goes.
"The only way to stop a bad guy with a gun is with a good guy with a gun"