I have heard from veterans of this site that while magnum primers are not required for .357 loads using 231, they can be more reliable as 231 tends to have a powder forward problem in the long case of the .357 magnum. I love using 231 for 38 special but it is a tad fast for .357 magnum.
Just ask rcmodel about punching a bowling ball to find out why?
Just ask rcmodel about punching a bowling ball to find out why?
