300WSM max load with H4831sc

Discussion in 'Reloading' started by Hurricane, Jul 26, 2013.

  1. Hurricane

    Hurricane Member

    Jan 17, 2012
    I am working with winchester m70 classic in 300WSM w/24" barrel. once fired nickel winchester brass, rem 9.5 primers Berger 185VLD Hunting bullets set at OAV 2.950. I see most manuals putting max load in the high 60g area ,, I worked up a load that has 70g of H4831sc . I am no expert but see no pressure issues . The primer shows no sign of flattening. Worked up a grain at a time from 60g all the way to 73 g with no primer flattening. I also shot factory load, win xpc3 180g , same day and that load flattened primer.
    I really want to use the 70g for Elk and that gets my Entergy around 1500 ftlbs out to 600 yds. The load also shoots 1/2 inch groups.
    Any thoughts?..
  2. backwoods83

    backwoods83 Well-Known Member

    Jan 8, 2011
    The best way to judge pressure in a short mag case is to mic the case at the web and check for over expansion. Btw unless the 185vlds are jammed in the lands, you will likely run out of room for powder with that bullet and H4831sc before it is over pressured, I don't even use a powder that slow under 208/210s in a short mag, I use Imr4350 or Hybrid100v. It also takes closer to 70k psi to notice over pressure issues with winchester brand nickle cases.
  3. lloydsmale

    lloydsmale Well-Known Member

    Feb 5, 2012
    what i sometimes will do is load the same piece of brass 3 times. If the primer pocket is still a snug fit for the primer your probably ok.