Woodleigh make 350gns bullets for 375 but who told you that 350 grain bullets works best in Flanged Mag ???????????

350gns have only recently really come into favour for the Magnum Bolt action rounds.

Use 270gn or 300gns or whatever your DR was regulated for.

if anything, AFTER you have sorted out a standard regulation load, go for a lighter load as unless you are after Buffalo or Elephant, a lighter load it is much more useful (ie 75% rule type load - so about 235gns).

375H&H dies can be used for neck sizing but I would buy a set of Flanged dies.

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