Reloading 300 WSM

Discussion in 'The Ammo & Reloading Forum' started by mark95138, Sep 10, 2008.

  1. mark95138

    mark95138 New Member

    Sep 10, 2008
    I am now the owner of a spicy custom 300 WSM. After around 80 rounds, (and saving all of my shells), I'm ready to start looking into reloading so I can afford to shoot this beast.

    A couple of things.

    I mic'd my empty shells (they're the steel casings from W.) and they are bigger by 5 mils on the neck, 10 mils on the body, and 10 mils in length. Any recommendations on resizing? I'm thinking I want to get the single stage RCBS - what dies to I need for resizing and in general?

    Also, I notice the neckdown portion is pretty distorted - not deformed, just looks like it expanded into the cylinder. Do I need to do anything here? Neck turning?

    How many time should I be able to reload a casing?

    Any help or direction folks can give me is appreciated
  2. LDBennett

    LDBennett Well-Known Member

    Dec 20, 2003
    Hesperia, CA

    What you need to do is buy the Hornady reloading manual. It includes a very good section on how cartridges cases work in guns with good illustrations. But here is my crack at explaining it.

    When the cartridge goes off because the primer starts the powder burning, the pressure get astronomical and push the brass into the chamber walls hard. As the pressure rises, the case, which is really a gas seal for the chamber, stretches in length to fill the chamber. The case distorts in diameter and length from the tremendous pressure. When the pressure subsides the brass springs back somewhat but not to the original sizes but slightly larger.

    To reload that case it has to be pushed down to a size that will fit all guns of that caliber. Sizing dies push the outside of the case to that smaller dimension and then the depriming pin, which is also the throat sizer, is pulled back through the case neck to make the inside diameter correct to accept an industry standard bullet. There are more details to the reloading, like case trimming, which insures the cases are not too long for that standard chamber. Neck turning is an advanced technique used for rifles not made to standard specs but with tighter chambers for bench rest competition.

    Pistol cases can be used almost indefinitely while rifles case can be used for somewhere between two to 10 times or more, depending on the caliber. Typical hunting calibers (30-06, 308, 270, 243, etc.) are good for maybe 5 relosds total whereas magnum cartidges (like 7mm Mag, 300 Win Mag, all belted cartridges, etc.) are good for maybe two reload or less. It depends on the relaoding techniques, and your gun. The problem is the constant working of the brass work hardens it and the necks will crack or, in the case of some magnums, either the neck will burn through or the base will seperate from the body (you must learn to recognise the indicators or you might get a face full of hot gases). But it is all in any good reloading manual. Just read, read, and re-read until you understand how it all works. Don't buy anything until you understand how it works!


  3. steve4102

    steve4102 Former Guest

    Jan 27, 2006
    Steel? I think you may have "nickel plated" brass. Reloading is a great hobby, I'm sure you will enjoy it immensely, but you should first get yourself a good manual and read it. Not just the back half that pertains to load data, but the first have that gives you the step-by-step loading process.

    Good luck and welcome to the wonderful world of handloading.
  4. mark95138

    mark95138 New Member

    Sep 10, 2008
    Thanks for the replies...I have the Sierra reloading book, and will buy the Horndy book you recommend.

    read, read, read, and reread - I heard this from several folks.

    really good info on the life of cases the 300WSM is a pretty wicked round so I'm pretty sure I need to learn what to look for very carefully...I don't want to ask what happens when the pressures colimb to 60K psi and things come apart...

    You are right...nickel plated brass - now my knowledge is really showing....thanks!
  5. steve4102

    steve4102 Former Guest

    Jan 27, 2006
  6. Falconry

    Falconry New Member

    Dec 1, 2008
    I started reloading my A-Bolt SS using Barnes 165s and a selection of powders. I ended up having H414 be the best powder for that weight bullet,even when I changed over to Hornadys for cost. I do need to try IMR 4350 a little more,especially if I decide to go up to 180 grain projos.
    I have been using Remington brass and CCI Mag primers. I haven't used the nickel plate brass for reloads, not sure if they don't harden after firing.

    I've only been neck sizing the reloads because I'm only loading for my rifle.

    The Barnes bullets are great on game,just pricey and my groups weren't super tight, but still easily MOA.
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