SmallCaliberCentral

I have a cooper mtv .204 on order. It should be here in a month or two. I have been able to purchase 1000 7 1/2 bench rest primers. I already had a good stock of Winchester WSR primers. When the 7 1/2's are gone,are the WSR GTG in the cooper ?

Thanks
J-Rat

The only safe way to answer that question would be to start over with your loads. If you are shooting under max just change the primer & try it. If you are near or at max then reduce 10% & try the WSR's.

A bad day at the range trumps a good day at the hospital.

a couple of good reads on primers and differences that changing brand and even batch can make

http://riflemansjournal.blogspot.com/20 ... study.html

http://riflemansjournal.blogspot.com/20 ... study.html

As Glen noted I would make sure you reduce your loads or start over to be safe. I would always recommend using a magnum type of primer for cartridges like the 204 ruger or any other high pressure cartridge. I only use 3 different primers for the 204: Rem 7 1/2 BR, Tula Small Rifle Magnum, and Wolf Small Rifle Magnum. Using these primers i have never ran into any problems with the 204 even when loading hot. I remember looking at a breakdown of the different primers and the Rem 7 1/2's have the thickest cup, i believe the Winchester SRP's were a little bit thinner.

Thanks everyone for the reply's

J-Rat