Hi, do you use regular or mag primers? Reloading manuals suggest to use mag primers, but I'm curious...

wildboar ----- My .270 WSM is most accurate with Federal 210M primers. I tried the 215M for months and comparing targets, the 210M won out in the end. Good luck and good shooting.

I load for the 270 WSM and the 300 WSM both and use only the Fed 215M primer.

According to the previous poster, maybe I am missing the boat by not using the Fed 210M, but that is a fairly large amount of powder to light and I am getting good groups as is.

I've used only standard force primers,(winchester LR), in my 300 WSM. I don't see the need for magnum primers, no matter what the cartridge designation is.

If we were to be using a pile of the ultra slow magnum powders, in a long narrow powder column, then a mag primer is needed. But most of the powders I use are midrange extruded powders, AND the big fat powder column is easier to ignite.

I use BR-2s in my 300WSM.
On the couple of loads on which I did side by side load development the Fed 215 were the least consistant and the Fed 210Ms were a close second to the Br-2s.
Others have had different results (as noted above).
Only your testing will tell you what your rifle likes.

The Powder column is short so, I use WLRs. Don't think you need the Mags but, they will not hurt anything as long as the load isn't too hot. May even help accuracy. Try em' both and see which groups the best.

Good Luck

Reloader

When I started with my 300WSM the only data that was out used WLRM primers. I got started with them, found good to excellent loads with powders from H4895 through 4831 and never bothered to try anything else.

They probably aren't really needed, but they worked for me... Try them all and see what works for you.

quote:

Originally posted by Reloader:
The Powder column is short...

BINGO! That is the key. Short and fat can benefit from standard primers. Either primer will work but the benefit of a standard/non-mag. primer is that you will get a more uniform burn from the flash hole to the shoulder. This is one of the "tricks" some high power and bench shooters use for accuracy. I don't believe there is so much powder in these short mags, especially the SAUMs, that a mag. primer is critical. I've used both and 2 of the best loads use Gold Medal Fed210M.

I have had good luck with both Winchester Large Rifle Magnums and the standard Federal 210, with the Federal 210 providing slightly better results with my loads in a .270WSM. If it makes you feel better, I have been told by a reasonably reliable source that worked in a ballistics lab for 4 years that the Federal 210 standard primer is just as hot and long burning as other manufacturer's magnum primers. They sure work well in my .270WSM.