7mm Dakota?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by craigf, Feb 16, 2012.

  1. craigf

    craigf Well-Known Member

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    Rattling around the idea of having a 7mm Dakota built. I am looking for the pros, cons, and general feelings on this particular cartridge. Thanks for any input.
     

  2. Rimu

    Rimu Member

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    I quite like this cartridge, nice balance between velocity and powder and it should give pretty good barrel life also. Had one built out of a rem 700 with HS bottom metal to get it feeding real nice. Rifle shoots 162 amax at 3200 fps into 1/4 inch at 100 m. 180 berger at 3100. So plenty of hitting power out there. Down side is the spendy brass, dies arn't too bad if you get a redding set from sinclair. Good luck
     

  3. Stumpm2

    Stumpm2 Well-Known Member

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    I had one built because I wanted a 7mm that could reliably push the 180 grain Bergers over 3000 fps with ease, but still easily feed out of a magazine with the bullets seated out long. I had not had my Dakota very long, but I already really like it and prefer it over my brother's STW. Spendy brass is the only real downside, but it you are building a custom rifle, the cost of brass is of little concern/overall cost to the project.
     
  4. Capstick

    Capstick Well-Known Member

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    I am having one built right now. I like the case. The funny thing is people complain about the cost of brass. Brass is a small part of the equation when you think about rifle, optics, gas, truck, and so forth.
     
  5. steelshooter

    steelshooter Well-Known Member

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    What are your load details?
    I am interested in the 7mm Dakota as well. How does it compare to the 7mm RUM?
     
  6. craigf

    craigf Well-Known Member

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    So not any negatives so far, I like it. I might do the opposite and get the brass and dies before I have the rifle started. At least then I am committed.
     
  7. LouBoyd

    LouBoyd Well-Known Member

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    The 7mm Dakota has 89 grains case capacity. The 7mm STW has 97 grains and the 7mm Rem Ultra has 112 grains.
    However, the 7mm Dakota can comfortably handle properly seated heavy VLD bullets like the 180 grain Berger from a 3.6" magazine (like a Rem 700) which the 7mm STW and 7mm Rem Ultra cannot. The 7mm Dakota case is only 2.5" long, like a 7mm Rem Mag.
    But beware, the 7mm Dakota only has a 3.33" SAAMI spec cartridge length. If you want to use it for long range make sure you get it in a rifle with a longer than SAAMI spec magazine. 3.6" is comfortable. A 3.34" magazine is not.
     
  8. rcdinaz

    rcdinaz Well-Known Member

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    It is a great round and the only downside as stated is brass is spendy but the Dakota brass seems to be pretty god stuff, no Lapua but pretty durable so far.

    I have been using H1000 @ 75 gr and average is 3,060 fps w/ 180 HVLD's
    Also tried Retumbo and settled on 73gr but it was just under 3K fps

    I had much more consistent MV with the H1000 but I am in AZ and the summer heat is a pain. I know they are both extreme powders but the H1000 seems to be more stable in very high heat. Now that my gun has just over 150 rounds down the tube I may check Retumbo again as some are loading as much as 77gr and getting 3,200 fps or more.

    Here is the Berger load data all are pretty conservative but give a good starting point:

    BulletPowderStart LoadApproximate Start VelocityMax Load Approximate Max Velocity Fill Ratio168 GrainH4831 SC64.5274770.0297791.5%168 GrainIMR 7828 SSC63.0276268.6300190.2%168 GrainRE 2565.5278471.1300096.5%168 GrainAA MAGPRO66.0274872.0300391.7%168 GrainRETUMBO68.0278474.0301499.4%168 GrainRamshot Magnum68.5275774.7301393.8%168 GrainVIHT N56063.5278168.9300989.2%168 GrainWW WXR63.5277068.7298190.3%(COAL - 3.330"; Barrel Length - 26")BulletPowderStart LoadApproximate Start VelocityMax Load Approximate Max Velocity Fill Ratio180 GrainH4831 SC62.5266167.8287790.5%180 GrainIMR 7828 SSC61.0267466.5290489.3%180 GrainRE-2563.5269668.9289995.5%180 GrainAA MAGPRO64.0266769.8290890.8%180 GrainRETUMBO66.0270071.7291398.3%180 GrainRamshot Magnum66.5267972.2291993.0%180 GrainVIHT N56061.5269466.7290988.1%180 GrainWW WXR61.0266166.6288489.4%
     
  9. rcdinaz

    rcdinaz Well-Known Member

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    Well posting the load chart looks like a mess! It should read like this when you line up the headers:

    Bullet ------------------ Powder --------- Start Load --- Approximate Start Velocity -- Max Load
    168 Grain -------------- H4831 SC -----------64.5 ------------------ 2747 ------------------------------70.0


    Approximate Max Velocity ------------ Fill Ratio
    ----------------- 2977 --------------------------- 91.5%
     
  10. Stumpm2

    Stumpm2 Well-Known Member

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    I am using 77 grain of Retumbo with the 168 grain Berger VLD's at 3,160 fps. I loaded up to 79 grains of Retumbo at 3,250 fps, but started to get high pressure signs and settled in on 77 grain. I will be experimenting with the 180 grain VLDs soon and hope to use Retumbo, but I will also try H1000. I get more velocity out of my Dakota (with a little less powder) than my brother does in his STW and more velocity than factory rounds out of an Ultra Mag with much less recoil.
     
  11. Stumpm2

    Stumpm2 Well-Known Member

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    RCDINAZ - Retumbo is slower burning than H1000 so you should be able to load a few more grains of Retumbo than H1000 for the same amount of pressure. If you are using 75 grain of H1000, I would think you could load at least 75 grains of Retumbo probably 76 or 77 grains.
     
  12. yomill

    yomill Member

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    Just had Nate Dagley, from Straight Shot Gunsmithing, build me a 7mm Dakota. Process took about 15 months or so, with barrel taking bulk of time. Defiance machine action, Bartlein barrel-5R rifling, Jewell trigger, Williams bottom metal. Accurate Innovations did stock work. Have yet to shoot it due to a hand injury, but am working up loads with 160 gr Northfork Bullets, and Swift A-frames for comparison. Folks at Dakota Arms advised that they use a lot of RL-22 in their production ammo. Plan on trying H4831Sc and Norma MRP also. Best idea is to buy a bunch of brass from Dakota as you get a bit of a discount for orders over a certain minimum. Will post some load info and accuracy stuff once I get at it. Special orderd dies from redding, but I think you can get RCBS through Dakota Arms website. Rifle is quite heavy as a result of wooden stock and #15 barrel contour but it shoud be a tack driver.
     
  13. craigf

    craigf Well-Known Member

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    Thanks to everyone who has replied thus far. I appreciate all the great input. I asked a gunsmith which would he build, a 7mm stw or a 7mm rum, and his response was. Neither, if it were me it would be a 7mm dakota. I am in the process of ordering the dies and Brass (back ordered) as soon as that happens I am committed. Looking forward to more input.
     
  14. rcdinaz

    rcdinaz Well-Known Member

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    I ran Retumbo up that high when I started but I had better consistency with H1000. Once I got over 3K fps I was happy the extra recoil and noise were not worth another 100fps, but that is just me. I haven't check my logs but I think I had H1000 test loads up to 76.5 as well.

    Load development will be on hold until I get my new 7mm RM set up. I am going to use the 168's in this gun.