Originally Posted By: GofaaastStart at minimum loads and work up. If you have access to a chronograph this is a great time to utilize it. Federal 215’s are know to be the hottest magnum primers so if yours are such keep that in mind. See if you can trade someone in your area for the primers you need.
Indeed start low and work up your Loads with the Magnmum Primers . If you have access to Sierria's Reloading data (5th edition) they give fed 215 in the load data for their receipes. but there again everyone will say to use the starting loads to check for pressure.which is wise.
I have had good luck with IMR4064 215 primers and 140grs bullets. good accuarcy, deer DRT. My Son still uses this load for his deer hunting when i handed him that rem 700, dies etc to roll his own.
here is a link to sierria's newer publish data for that cartridge which includes the newer powder and bullets for the 7 mag. (they changed to Winchester Mag Primers for the data)
https://sierrabullets.files.wordpress.com/2018/03/7mm-remington-magnum2.pdf
But one Can use Plain Large Rifle Primers by using powders that are normally used for say the 30-06/ 308.
What is the real differance is the primers ability to ignite the charge. given a couple of varibles 1. amount in the case (relativilive to the powers burn rate), 2. and ambient temperture. Again work up the loads everytime you change a componet. not only are the magnum primer "hotter" they have a thicker cup.
over the years I have used LRP and Mag LRP in loads in that and other cartriges.
for a visualation of primers see here
https://www.6mmbr.com/primerpix.html
another link cncerning primers
https://carolinafirearmsforum.com/index.php?threads/the-primer-on-primers.77416/
and another discussion from across the pond
http://www.targetshooter.co.uk/?p=1471