Started to load some .358 win yesterday and I noticed some previously primed brass had a silver colored primer the ones I primed with WWlarge rifle had a copper color. I thought I had used the same in all loads.

Anyway, which primer is best for standard loads (usually compressed) CCI, WW, or Remington. I want one that will go boom every time,and ingnight the compressed charge without increasing pressures. Do I need a magnum primer ?

Pretty much any box of new primers will go boom every time. You don't need a magnum primer for that cartridge but I doubt it would hurt if you start the load development process using published load data from a load book. Start on the low end and work up and watch for pressure signs.

Maybe the other cases were primed with the older WLR's? W-W's were a silver color for as long as I can remember (from when they were called 81/2-120's) until a couple years ago, they changed to a copper'ish color.

I've had the best luck in my 358 with CCI-200's, the only rifle I have using LR primers that prefers CCI's. Try a couple different brands, preferrably with a starting load, then stick with whatever one performs best for your remaining load workups.

R-WEST

Winchester WLR primer is what worked best for me.

As for the color of the primer, old WW primers were silver, new ones are copper.

Winchester WLR

I've long used nothing but CCI primers, with perfectly satisfactory results.

I reload for 11 different calibers and use them all, rarely noticing any difference. One year I loaded up quite
a few different rounds with the only variable being the primer. It there's a difference it escapes me. There
are probably several different opinions on this, but I don't think any of them are definitive.
Best wishes.

Cal - Montreal