Ive been using Winchester Large primers which can be used for both standard and magnum. I doubt theres much difference if they can do one for both needs. Been using them in my .44 MAG and .45ACP
Primers can cause changes to your load and pressure signs. If you're loading hot pistol rounds near the bleeding edge of max, I'd take it down a notch before switching to magnum. If you're just loading general below listed max or plink loads your not going to see any change.