[Smokey Joe]

Rangermonroe--Which primer? Simple. You use pistol primers in pistol rounds and rifle primers in rifle rounds. Large versus small primers--Easy! The smalls fall out of the large pockets, and the larges won't go into the small pockets.

Some rifle and pistol primers are the same size and will physically interchange--DON'T DO IT! You will either have reliability problems or overpressure problems.

Magnum vs. "regular" primers?? Still pretty simple. Follow the reccommendation in yr loading manual. For a given bullet, with a given powder, the manual will say, for example: "For this load, magnum primers are reccommended." There, you use magnums. If it doesn't say, you probably want regulars.

All the powder manufacturers have websites, and will respond to questions about which primer to use in a given application if there is a question. Sierra Bullets is also really good on reloading questions.

There is one complication: Winchester Large Pistol primers are reccommended by Winchester for both magnum and non-magnum applications. I suspect that Winchester just wanted to cut down on the different kinds of primers they were making. But these work for me in my .45ACP target loads, which is all the use I have for Large Pistol primers.

For rifle shooting I like "benchrest" level primers, just for the increase in uniformity. Maybe doesn't make a real difference, but for me there is a mental difference.

I've used Win, CCI, and Federal primers, all successfully. I don't like the Federals just because the huge boxes in which they are packed, take up extra space in my cramped reloading area. But the primers themselves work fine.