7mm stw mag well to short

Discussion in 'Gunsmithing' started by skinny pedal, Nov 10, 2013.

  1. skinny pedal

    skinny pedal Well-Known Member

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    I have a savage 112 in 7mm stw that I want to have a longer mag well installed so I can load the rounds long enough to get near the lands . the factory mag well says 300 win mag which is way shorter than the 7 stw
    thanks for any input you can give me.
     
  2. J E Custom

    J E Custom Well-Known Member

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    The 7mm STW is a high intensity round and I would recommend staying away from the lands not
    getting closer.

    If you want to extend the mag so you can shoot factory loaded 7 STW ammo that is fine, but stay with the SAMME
    free bore.

    Free bore is your friend when it comes to velocity and holds the pressure down. It also does not
    help accuracy like in some of the milder cartridges.

    All of the new high pressure rounds (65,000 + PSI) have lots of free bore but are still very accurate.

    You will find that the Berger's will be very accurate .080 to .100 thousandths off the lands and allow for high velocity (The reason for going to cartridges such as the STW).

    This is just my opinion for what it is worth.

    J E CUSTOM
     

  3. mark fox

    mark fox Banned

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    Dec 18, 2012
    You could extend your box or cut of three threads re thread & rechamber with a shorter lead. having the ability to seat form .000 to .045 is what you want. having a rifle that you cant make accurate with any bullit design is what you want. preasure is what ever you make it. But if your cartrage is not accurate due to too much freebore thats not good not many people have a use for a single shot bolt action in 7stw.
     
  4. skinny pedal

    skinny pedal Well-Known Member

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    thanks for the info. I havent shot it to much yet but i was assuming that i needed to get the bergers just off the lands like i do with my 6.5x284 to make it shoot accurate.
    I just had Sharp shooter supply flute the barrell and install a muzzle brake as well as blue print the action so it is on its way to being a good shooter i guess i should look at bullets that it will shoot rather than a longer mag. well.
    also i loaded some 162 hornady a max and i cant seem to get them to stay tight in the brass and they dont have a crimp groove. i can push the bullet in and pull it back out with my fingers. any idea on what i need to do different on that ?
    thanks for the input
    casey
     
  5. Iclimb

    Iclimb Well-Known Member

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    Is the expander in your reloading die too big?
     
  6. skinny pedal

    skinny pedal Well-Known Member

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    Not sure . It seems to hold the 168 bergers fine ???
     
  7. J E Custom

    J E Custom Well-Known Member

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    I would recommend getting a set of Redding bushing dies so you could change the neck tension on the bullet.

    You can get different bushings for the dies and adjust the tension .

    J E CUSTOM
     
  8. Trickymissfit

    Trickymissfit Well-Known Member

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    "JE" is right on the money about keeping the free bore and backing the bullets off the lands. When you get the bullets right onto the lands, all the load data becomes useless! Just like a no free bore .300 WBY mag. And we're talking about some extremely serious pressure spikes!
    gary