Help on barrel selection

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Frazer28, Mar 26, 2007.

  1. Frazer28

    Frazer28 Member

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    I picked up a M70 couple of weeks ago in 300 RUM and think I'm gonna rebarrel sooner than later. What do yall recommend on length, contour, and twist? I will probably shoot 180-220 gr bullets 90% of the time, but would like to play with some 240's. I also want to add a brake and would like to have it blend in with the barrel contour. I'm not overly concerned with weight but also dont want a boat anchor either. Kinda got long winded, but Id appreciate anyones input.
     
  2. James Jones

    James Jones Well-Known Member

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    Considering your caliber and bullet choice I'm assuming your wanting a long range rig.

    If it were mine I'd go with at least a 28" barrel probably 30" ,Rock Creek #5LV conture fluted with a 1-10 twist.
     

  3. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    What model M70 did you get. This would determine which contour I would recommend.

    I would personally go with a Lilja 1-9 if you want to shoot the 240s. A 1-10 would be right for the 180-220 gr pills but since you want to try the 240s a 1-9 will be needed.

    I would personally say stay away from the 240s. The reason is because the newer, lighter long range bullets will get you nearly the same BC but with a higher velocity potential and allow you to stay with the 1-10 twist but thats just my personal opinion.

    Barrel length, if your going with a sporter rifle, 27" would be about max I would recommend. In a Lerado type rifle I would say you may be able to push 30" but the barrel shank on the M70 is pretty short and small in diameter so I may limit it to 28" just to be safe. That is plenty of barrel for a 300 RUM.

    I would recommend a Defensive Edge brake. The diameter would depend on the barrel contour you go with. Matching the muzzle brake diameter to the muzzle diameter may be an issue on the lighter contour barrels.

    I would much rather have a slightly larger diameter brake and get the benefits of a partition style brake like the DE brake then get a brake to match the barrel diameter and be limited to the performance of a brake such as the Vias.

    Just my opinion.

    Kirby Allen(50)
     
  4. Frazer28

    Frazer28 Member

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    It's the M70 classic, so if I went with 1-10 that should pretty much cover everything then? The barrel on it now is way to flimsy for my liking, I was thinking maybe a #6 sporter contour fluted or possibly a 7 or 8 straight taper fluted, my thinking is maybe that size would match up well with the DE or Holland brake. I'm new to all this so thanks again for the reply's, its amazing what you learn when you actually listen.
     
  5. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    JFC,

    A 1-10 will handle anything up to say a 220 gr SMK but nothing much heavier. If you want to shoot the 240s you will need a faster twist such as the 1-9.

    If you plan on using the factory stock, you will be limited in what you can use as far as barrel contour. In most cases, I would say the #7 or #8 will be far to large for the Winchester Classic sporte stock forend.

    Even the #6 will be tight in the area at the end of the full diameter barrel shank just ahead of the receiver.

    Now if your looking to get a new custom stock, you can get one to handle any barrel you want to use.

    A #7 Lilja will finish up very closely to a DE 0.875" diameter brake. Close enough that you can turn the brake down a small amount to match. The #8 is larger and will need the 1.000" DE brake and it can not be turned down to match that barrel muzzle diameter.

    Kirby Allen(50)
     
  6. 308 nate

    308 nate Well-Known Member

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    JFC,
    My recommendation on barrels would be either the Broughton 5C's or the rock Creek 5r's. I would probably go 9 twist with Broughton and 9.5 with the Rock Creek.

    Barrel length....28-29" you could start with 29" and then move the chamber ahead once the barrel is loosing accuracy.

    Contour.... I kinda like the Palma contours as they have a little more length of straight cylinder on the breech end which allows the barrel to be set back a few times. The number 5 contours are also good contours.

    Muzzle brakes.... Of course since I make muzzle brakes, I'm going to recommend my own /ubbthreads/images/graemlins/grin.gif but the D.E and Holland brakes are also good quality brakes.

    I also offer my "V" brake in .875 and 1. I can match barrel contour in between sizes without changing port sizes for no additional cost. Here is a picture of a "V" brake I just installed on a rifle with a muzzle dia. of .890

    FWIW,
    308nate


    [​IMG]

    [​IMG]
     
  7. Frazer28

    Frazer28 Member

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    Thanks Nate, thats a nice looking setup.
     
  8. wildcat

    wildcat Well-Known Member

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    308, nice looking brake.
     
  9. James Jones

    James Jones Well-Known Member

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    Not only is that a slick looking brake but it works very well also , I had Nate install one on a buddies Weatherby MK-V stainless synthetic chambered in 300Wby mag.

    The gun itself weighs 8.5 lbs , I got it back put it in the stock and went to test it , first shot I was choking the poor gun second shot I held it up to my shoulder and bumped the trigger letting it free recoil , just a slight bump , this thing only kicks like a med to heavy 243.
    I only planned to shoot 2-3 rounds but ended up letting 7 other people shoot it with equal amazement.
     
  10. remington 1

    remington 1 Member

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    JFC,
    I shoot the 240 gr Sierras in a Krieger 1-10 twist that I have on my 300 wby heavy gun and it simply shoots great (even at a relatively low velocity of roughly 2800fps). Originally I was facing the same dilemma and was about to order a 1-9 twist, but my gunsmith, who has been shooting and building bench guns around this combination for years, said he had never had a problem with the 10 twist stabilizing the bullets and thus convinced me to go in this direction.

    I know Sierra recommends a 1-9 twist for these bullets, but based on my experience of shooting thousands of the 240’s, and the fact that you are primarily planning on shooting the 220 class bullets, I would definitely stick with the 10 twist.

    Hope this helps!
     
  11. eddybo

    eddybo Well-Known Member

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    JD...it didnt hurt my gun any. Maybe yall got the misses out of it shooting it w/o sights. /ubbthreads/images/graemlins/grin.gif BTW thanks to you and Nate the gun now shoots great and the recoil reduction over the previous brake is substantial. BTW Mr. Don said Nate's work was top notch, that is a real compliment.
     
  12. James Jones

    James Jones Well-Known Member

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    Good deal , I'm sure Nate will be happy to take a complement from a Hall of Fame BR shooter and world class gun builder !!
    I'm about to post about the effectivness of the brake in the equiptment review section maybe you could chime in their if you don't mind

    I'm glad your happy with it
     
  13. BountyHunter

    BountyHunter Writers Guild

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    If you are going to use a large magnum, then the 1-10 would be the way to go. The 1-10 has been used quite sucessfully for years with magnums and 240s in the 1k BR game. Plus the 1-10 will really shine with the 190=220 class bullets.

    The 1-9 comes in if you are going to shoot at a much lower velocity such as the 2600-2700 range.

    BH