338 wsm

Discussion in 'Gunsmithing' started by graybullet, Jan 2, 2013.

  1. graybullet

    graybullet Active Member

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    Any of you ever neck up a 300 wsm to 338? If so what do you think about it. What speed did you get?
     
  2. cowboyarcher

    cowboyarcher Well-Known Member

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  3. Trickymissfit

    Trickymissfit Well-Known Member

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    would that not be the samething as a .338 RCM?
    gary
     
  4. cowboyarcher

    cowboyarcher Well-Known Member

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    300 WSM is a bigger case than the RCM by 8 grains or so, and the WSM brass has better availability and support.
     
  5. etisll40

    etisll40 Well-Known Member

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    I never thought of that possibilty, but with so may "Shadow" version model 70's on Gunbroker cheap, I wonder if a 300wsm 35 cal whelen would be doable. Now I have to check the case capacity vs 30-06. A short action 35 whelen would be a nice stomper for black bears and hogs in the woods and maybe out to 250.
     
  6. cowboyarcher

    cowboyarcher Well-Known Member

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    It's called the 35 Sambar in it's most common name I think. . .
     
  7. etisll40

    etisll40 Well-Known Member

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    Thanks, I'm going to follow this thread, a 300wsm-338 or 358 sounds interesting. I wonder how fast the 300wsm-338 with a 250 grain bullet from a 24" barrel will fly? What twist 1-10 I presume.
     
  8. Trickymissfit

    Trickymissfit Well-Known Member

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    I always thought the .338 RCM was nothing but a .325 WSM necked upto .338.. guess i was wrong
    gary
     
  9. sambo3006

    sambo3006 Well-Known Member

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    I've got a Kirby Allen chambered Lilja 10 twist barrel in 338 WSM I picked up for a possible rechamber to a larger case but I'm debating it. Very low round count and shot half moa when Kirby built the original rifle. I think the 338 WSM pretty much duplicates 338 Win Mag velocities out of a short action rifle.
     
  10. cowboyarcher

    cowboyarcher Well-Known Member

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    The WM has a case capacity of 84grn vs 81 grn in the WSM, so the WM should be just a touch faster. I think the WSM though will be more efficient and loos less velocity with barrel length than the WSM, so it seems to me a WSM could be a great round in a 18"-20" SA light weight rifle. . .
     
  11. J E Custom

    J E Custom Well-Known Member

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    It is very close to the same volume and its ballistic equal.

    As you know Ruger like every other company changes there case just enough to make it
    proprietary so they can sell there own ammo and brass.

    I looked at both the 338 WSM and the 325 Wsm and the 338 RCM was my choice because
    dies and reamer availability.

    I looked at all of the loading data for the 300/338 Wildcat and did not find any load with
    a 200 grain that exceeded the RCMs 2950 ft/sec and there was almost no data with bullets
    over 200 grains. So I decided to stay away from the wildcat with it's problems of sizing and
    fire forming and the head stamp difference.

    I love wild catting a case if it has something to offer more than other cases in its class.

    I had a 325 WSM that did not shoot that well,and the lack of good bullets and no more
    performance prompted me to go with the 338 RCM based on all of the advantages it offered
    and the price of ammo ($29.00 a box at the time compared to the 325s 45 to 50.00dollar
    a box.

    Potentially the 300/338 should be a little faster because of its slight case capacity advantage
    but I could not find it. Also Hornady loads there Superformance powder and the loads are
    Max.

    I have not tried 225s or 250s because if is at its best with the 200 grain bullets and bigger
    bullets need more case capacity. and with all of the good 338 bullets my choice would be
    ether the 300/338 WSM or the 338 RCM if a short mag was what you wanted.

    J E CUSTOM
     
  12. Frank7mm

    Frank7mm Well-Known Member

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    The 338wsm with a 30" barrel seated very long with 300gr berger will do 2600fps MAX 2500-2550 practical. It was very accurate. I gained some fps by using 7mm brass but a pain to neck up.
     
  13. graybullet

    graybullet Active Member

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    How far out have you shot it?
     
  14. Frank7mm

    Frank7mm Well-Known Member

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    Out to 1k. Held 1/2 moa.