Lee Loader

So yesterday I was at the annual Tulsa Antique fair. I spotted a dealer who had a box of Winchester small rifle primers from the 1960's - it was nearly full. The price was negligible so it came home with me. The box is nearly perfect so I expect the primers are too.

Has anyone used small rifle primers in 357 Magnum reloads? If so, I would like to hear your results and take on the matter. In my older reloading manuals, it specifies "Small Rifle or Magnum Small Pistol" primers with certain loads in this caliber.

You'll hardly notice a difference if at all.

A number of years back a obtained some primers (5000+) of the same vintage when my local GS was cleaning up his shop. I seem to remember only a few not going bang. Hope you have the same experience.

Rifle primer cups are said to be harder,, so a light pin strike could be a problem. I used some small rifle in 357s with my Contender and had no problems. That was however back in the 90's so it hard to tell how the metallurgy might have changed.

Make smoke,

Like Gas said, you'll hardly notice the difference, if at all

I remember reading somewhere a long time ago someone called customer support at CCI and questioned a tech about the difference between small pistol mag primers and small rifle and was told they are the same product in different packages.
I can not confirm the story ... but I have tried it both ways and it would seem to be true

Not sure if my experience is unusual but substituting one primer brand, type or even batch makes a difference measurable with a chronograph in rifle loads. I can't say for certain with handgun ones as I don't expect the same accuracy. I have owned two chronos and never measured a handgun load. Like everything in reloading, if you are pushing the max making a change calls for reducing the load and working back up.

When the primers were hard to find awhile back I did some research and found the CCI 400 Small Rifle Primers could be used in place of Small Pistol Primers. They do need a harder strike but they work just fine in mu: Ruger Security 9; S&S 65-6 in .38 and .357; 9mm Sig P365; and my SAR CM9BL10. No complaints or problems here.

Small pistol primers and small rifle primers have the same dimensions and can be interchanged in a a pinch.

Large Pistol primers and Large Rifle primers DO NOT have the same dimensions and cannot be interchanged. The cups are not the same hight.