6mm remington

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Shane1, Oct 28, 2013.

  1. Shane1

    Shane1 Well-Known Member

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    What is the preferred twist in 6mm for the heavy bullets. I've read bergers reccomendations just curious what's working best for you all. I'm thinking an 8 twist for a 26" barrel in 6mm should cover most all of the heavies. Maybe not the 115 berger. What are your thoughts. Would chambering to an ai gain enough velocity to possibly stabilize the 115's. I know nobody can say for sure but maybe some of you have stabilized the 115 with an 8 twist.
    Thanks, Shane.
     
  2. AZShooter

    AZShooter Well-Known Member

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    When my two friends and I made 6mms to shoot the 115 DTAC a 1 in 7.5 twist was recommended. A few said they could get the 115 to stabilize with a 1 in 8 but it was not the norm.

    We also discovered that there were issues with the 115 Berger VLDs not being able to withstand the twist when pushed hard with a 6mm-284. That left the DTAC as the only viable 115.


    1 in 8 will do fine up to 107 gr. Quite frankly I don't see an advantage in any of the 115s now that Berger offers the 105 match target hybrid with a BC higher than their 115 offering. .547 vs .545
    I will admit that the DTAC has a higher BC which is generally reported as .585 but the velocity is quite a bit slower.

    I get 3250 fps with the 115 DTAC and 3445 fps with the 105 Berger hybrid from my 6mm-284. The Berger's drift at 500 yds (10 mph crosswind) is 8.2" while the DTAC is 9.1" with same conditions of 4000 ft 59 degrees etc.

    I have a new Bartlein 5R 1 in 8 twist which will replace my current Bartlein 5R 1 in 7.5 twist when it begins shooting poorly. Round count is close to 1000 with good accuracy.

    I'll switch to the 1 in 8 and intend to shoot the 105 hybrids exclusively. FYI some hunters are reporting that the hybrid is working well as a hunting bullet. Go to bottom of the page:

    http://www.longrangehunting.com/for...er-takes-down-two-grizzlies-78901/index7.html
     

  3. Shane1

    Shane1 Well-Known Member

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    Thanks Azshooter, I was leaning toward the 1 in 8
     
  4. Edd

    Edd Well-Known Member

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    Velocity adds very little stability compared to increasing twist. Using the 115 gr Berger as an example, you would have to increase the velocity by 1400 fps to get the same effect as increasing the twist from 8.0" to 7.5".
     
  5. B23

    B23 Well-Known Member

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    I think there are certain cases that are just begging to be improved and IMO the 6mm Rem. is certainly one of those. I'm not exactly sure how much gain there is when you "improve" the 6mm Rem but I believe it's around 9-10% which is a pretty healthy jump in case capacity over factory dimensions.

    A 10% jump in case capacity would put it very close to the same as a 6-284 so then I would think why not just go with a 6-284 to start with and skip the fire forming, as well as the 6-284 has MUCH better brass quality.

    I have a slow twist 6-284 so I can't shoot the "heavies" but my dad has a fast twist 6-06ai that he tried both the 115's and 105's in. For him the Hybrid 105's were hands down the better shooting bullet.
     
  6. Shane1

    Shane1 Well-Known Member

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    I agree it would be just as easy to chamber to 6-284 as 6mm ai.
     
  7. B23

    B23 Well-Known Member

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    Shane1, also, I'm not sure about your area but where I live finding Rem 6mm brass isn't very easy. My dad has a TTH ie.22-6mm that uses the Rem 6mm parent case and finding brass for him can often be a pain and Remington quality brass is just OK at best, it's not even close to Lapua quality.
     
  8. Shane1

    Shane1 Well-Known Member

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    I agree. There is some 6 mm brass at my local gun store as of yesterday if you need me to pick you some up. I think I'll go the 6x284 route.