I have asked a few friends, and read both of my reloading manuals and still haven't found a definitive answer to my question. If working up a load say for this example for .223 and working up a load from the "starting" weight charge of powder, does it matter if you use small rifle primers or small magnum rifle primers? In my manuals it doesn't say you can't, it just says not to go to the magnums with near max loads that have been worked up with standard small primers. Can anyone answer this for me? Thanks

it doesnt matter, they arent necessary but shouldnt cause a problem. The caution is when a load nears maximum a magnum primer MAY increase pressure so as long as you work up with them checking for signs of pressure, you should be fine. i use magnums in my 22-250 most of the time, especially with ball powders like H335, H380, and BLC-2

Thanks for your help. That is exactly what I thought, but you can't be too careful. Better to ask the experts and be safe than to chance it an be sorry. Thanks again.

Mag primers can increase the start pressure so don't expect your altered load to act like much like the book load was reputed to have done.

In all the years I have been doing this, I have never improved a standard load (ball, shperical, stick or whatever powder) by using a magnum primer. And that's more years than I would care to admit.

well i have always read when using a spherical powder around or above 40 grains, or when it could be used in cold weather to use a magnum, so i have done it. My supply store also sells CCI 250s cheaper than 200s?