pros vs cons of extra long barrel 270 wsm

Discussion in 'Long Range Hunting & Shooting' started by Djohnston, Jun 3, 2014.

  1. Djohnston

    Djohnston Member

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    My idea is to put a 30in barrel on my wsm. I see how this can be tuff due to lack of printed data. I have people say as long as possible and a lot say 28in max.there must be advantages to both. Does anyone care to share there experience to educate me a little bit? I sort of understand the burn rate. It seams that the longer barrel with the right powder could give more accuracy. Any advice for me?
     
  2. jfseaman

    jfseaman Well-Known Member

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    What are you going to use it for?

    Target only, sure 30"
    Long range but you don't have to carry it to far, 28"
    Spot and stalk or backpack hunting, 26". Maybe shorter.

    Everything is a compromise. Longer can be more accurate with higher velocity but heavy.
    Medium 26-28, lighter and you give up ~50fps
    Shorter, could give up speed and maybe accuracy but will be lighter.

    I went 28 on my 300wsm. Sendoro profile. Heavy as 12lb+ but it shoots.
     

  3. J E Custom

    J E Custom Well-Known Member

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    There is a practical length that you reach with any barrel, (Velocity, Accuracy, and manageability.

    That being said, there is a point of diminishing returns. After an optimum length is reached (The length that the velocity per/inch of barrel starts to decrease adding more inches does not add much velocity and at some point depending on the barrel contour may/can start effecting accuracy due to the harmonics.

    The 270 wsm can certainly use a 28" barrel and benefit some from a 30". beyond that the increases in velocity will taper off.

    The main advantage you will see is when shooting heavy bullets. the longer barrel will allow the slower powder to completely burn as long as you use the right primer.

    As far as accuracy Shorter barrels are normally more accurate because the harmonics are better and the barrel is stiff. The longer barrels have more whip unless they are the heavy tapers, contours.

    Dan Lilja did a test on maximum barrel length and started with a 46" barrel and cut 2'' inches off
    between each test.

    Lilja Precision Rifle Barrels - Articles: Barrel Lenghts and Velocities in the 338/378 Weatherby Magnum

    Hope this helped

    J E CUSTOM
     
  4. chrishatley

    chrishatley Well-Known Member

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    My 7wsm has a heavy 30" barrel. I'm getting rather high velocities with a light powder charge. 67grns. H-1000, 162 amax, 3025 fps. I also have a "match" chamber. The only thing that sucks is I had to buy a longer cleaning rod.
     
  5. Djohnston

    Djohnston Member

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    Thanks J E Custom. I'm a bit limited on this project. I have a heavy bull 30in barrel I will use. I intend on using a tight neck with a little through. I really like the 135 match kings but I think I will need a heavier bullet for 1000yd. I have heard nothing but good about matrix vlds. I'm just starting to select a load for this rifle. Any thoughts?
     
  6. Djohnston

    Djohnston Member

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    Thanks J E Custom. I'm a bit limited on this project. I have a heavy bull 30in barrel I will use. I intend on using a tight neck with a little througt. I really like the 135 match kings but I think I will need a heavier bullet for 1000yd. I have heard nothing but good about matrix vlds. I'm just starting to select a load for this rifle. Any thoughts?
     
  7. Djohnston

    Djohnston Member

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    Thanks Chrishatley. If you don't mind my asking. What kind of range and accuracy are you getting out of your 7? A while ago I made the mistake of shooting my buried rifle at 1000yds. Boy did I get bit! What a learning curve. Thanks for your comments.
     
  8. Djohnston

    Djohnston Member

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    Thanks Fjseaman. This rifle will be for shooting paper or fun only. Thanks for your comments. I appreciate any advice you have for me.
     
  9. jfseaman

    jfseaman Well-Known Member

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    If it were me, 28", fluted, sendoro or varmint taper. Shorter would be OK but if you get a 8 twist for those matrix vld 180s, I think you'd want the 28" for as was said the slow powders.
     
  10. chrishatley

    chrishatley Well-Known Member

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    At 100 yards, it shoots 3 rounds into the same hole. Most of the time. Looks similar at 200. I have shot around 400 rounds of this load at 1000 yards. I'm shooting at a steel cut out of a prairie dog, and normally hit at least 3 out of 5 shots. Reading wind, and mirage is definitely an acquired skill...
     
  11. Djohnston

    Djohnston Member

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    Wow! Impressive!!! What bullets have you found that your 7 likes ?
     
  12. chrishatley

    chrishatley Well-Known Member

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    It seems to like 162 amax better than anything else, but shoots Sierra 160 game kings pretty good too. Berger 168grn were on par at 1000, but not as tight closer.
     
  13. steeltraps

    steeltraps Well-Known Member

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    I have a stainless Tikka T3 in 270 wsm. I shoot 140 gr bergers at 3300 fps. I have a 4x16x50 pst Viper on it , and have shot it out to 600 yards. It only shoots about 1 moa at that distance but it a sporter weight barrel, and one of my treestand guns.
     
  14. Djohnston

    Djohnston Member

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    Hey J E Custom. Thanks for the link ! Great read. Tho I may read it again. A lot of bits of info there. Thanks for your help.