6mm Grendel...?

Discussion in '6mm, 6.5mm, and .25 Cal (Not 6BR)' started by Sniper338, Nov 12, 2014.

  1. Sniper338

    Sniper338

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    6.5 grendel necked down to 6mm.... I know it's been done, I've read some stuff that I have found playing around online...

    Has one here personally done it, have any experience with it? I know some call it a 6mmAR, then ackly improving that on top of it all...

    It has spiked my interest for a few years now... I have been running a 6.5 Grendel that I built a few years ago and it's just been one of my best shooting guns I own still to date. No benchrest stuff here, no competitions, just looking for input on maybe doing this. I'm a sucker for the little cases like this, but I still dont even own a 6br haha!
     
  2. DHD

    DHD Silver $$ Contributor

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    Type in 6mmAR.com and read all about it. Robert Whitley (he posts here every so often) makes the things and should have just about everything you want for it. There was/is the 6mmAR, 6mmAR Turbo, and 6mmAR Turbo 40. I think he only makes the 6mmAR and 6mmAR Turbo 40 now.

    Been shooting the Grendel or quite a while myself.....
     
  3. Sniper338

    Sniper338

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    yes sir you are correct. I contacted them already this afternoon. I was just seeing if anyone had some hands on experiance they could share!
     
  4. 5spd

    5spd

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    Im pretty sure you will be a happy camper if you build on off the stubby case. Many out here have done so and they are accurate as all get and slam everything from p-dogs to Deer.
    When I was looking at doing a 6mm Grendel I searched all over and saw there are a lot of variations and with my build I went with the 6.8spc necked to 6mm (6x6.8 ) or 6mm spc.
    The reason I went that way was a more fps & components/dies/ data was already around & no fire forming at all, just a neck down and load. I was not planning anything over a 95g bullet also and mainly a coyote/antelope rig.
    My build ran under $600 for a new complete upper I assembled.
     
  5. Rtheurer

    Rtheurer

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    6mm Rat or 6mm Fat Rat is a 6mm based off the 6.5Grendal case. You can search that one as well. Mine shoots pretty dern good.
    RussT
     
  6. tonysnoo

    tonysnoo Silver $$ Contributor

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    We have four in our crowd...two 6mm ar and two 6mm fat rats. Check this web site as an option. http://www.accurateandreliablerifle.com/products.html
    The formed cases measure very very close to each other.

    The performance is great! We have been shooting them all season in a local 200 yd to 850 yd steel match that is generally dominated by bolt guns. These little guys held there own and won a few...just makes a guy grin even more.

    Build it...you'll love it!
     
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  7. tonysnoo

    tonysnoo Silver $$ Contributor

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    LOL

    Russ and I must have been typing away at the same time
     
  8. 6brxdude

    6brxdude

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    I went with the 6mm Fat Rat from Lee Wells. I selected a 22 inch Kreiger barrel with 1/10 twist to shoot coyotes with using 70 grain Noslers. 3385 fps using CFE223 from my Magnetospeed with less than 15 fps deviation.........very surprised! Took it to the high-power silhouette range to fire form using some cheap Midway 87grain bullets. The Rams at 500 meters and the turkeys at 385 meters were boring once I learned holdover on my Leupold 3x9 VR scope. I'm not much of an AR fan but it is handy when you're humping around in the Arizona desert. Its a very accurate round although it did take some trial and error to get the right load and buffer to keep ejection reasonable.........recoil is negligent. Waiting on a Thunderbeast 30P-1 suppressor for this rifle........could be a game changer for me

    Kevin
     
  9. TikkaSporter

    TikkaSporter Silver $$ Contributor

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    I've ran a 6mm AR Turbo 40 from Robert Whitley since 2011. It's taken a mountain of coyotes, including one at 750 yards, numerous antelope, and 5 mule deer.

    I use 105 gr A Max's at magazine length going 2810 fps. That load is plenty accurate, but a little hard on the brass. I fire-form with 87 gr V Max's and they work just fine for plugging coyotes, other than having to crawl around in the snow trying to find every piece of brass after emptying a mag on a runner :)

    Overall, I'm pretty happy with it. It was a little finicky on load work up, but shot well once I found the right combination (Varget & Rem 7 1/2 primers)... For some reason mine just didn't like the CCI BR-4 primers as much as the Rem 7 1/2's...

    I had it built with a 25" krieger barrel and a lighter than standard contour (.750 to the gas block and 0.730 to the muzzle), which balances the rifle really well. Heavy billet upper & no side discharge handle.

    I'll see if I can dig up some pictures in a bit...
     
  10. TikkaSporter

    TikkaSporter Silver $$ Contributor

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  11. Sniper338

    Sniper338

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    Good info... its something ive been toying the idea for a long long while. Im not a huge AR-15guru, but my 6.5 grendel has performed so well for me that it makes me think twice about how accurate an AR platform can really be nowadays...
     
  12. rogn

    rogn Silver $$ Contributor

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    Could a 6PPC work?
     
  13. tonysnoo

    tonysnoo Silver $$ Contributor

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    I don't know why it wouldn't. Same basic cartridge. These are just blown out a fair bit more.

    I often wondered about using and forming brass like the PPC guys do, but Grendel brass is so easy.
     
  14. mchees1

    mchees1 Silver $$ Contributor

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    I happen to have a 6mm BR body die that works very well and in one pass to resize my 6.5 Grendel brass down to 6mm AR. I adjust the die so that the sizing stops at the shoulder. I measured with a shoulder bump gauge to verify that the die was at the correct distance. The first photo shows the original 6.5 Grendel case and then the second photo is the case necked down to 6mm with the body die. The green marker was also used to visually verify the correct setting. The ID of the case is about what a fired 6mm case is - a 6mm bullet will go down into the neck with just a bit of friction. Then to finish, I use a FL 6mm AR bushing die form Redding to get the ID to what I want. No damage to any brass.
     

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  15. topsail86

    topsail86

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    Been shooting a straight 6mmAR in High Power matches for the last couple years. Varget and 107 Moly SMK is the magic out to 800 yards.
     
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  16. Tim Singleton

    Tim Singleton Gold $$ Contributor

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    Is this project on a gas gun or a bolt gun?

    Either way mike ezell has a lot of experience with 6 grendel
    @gunsandgunsmithing
     
  17. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    243lbc
     
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  18. Varminterror

    Varminterror

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    I put together a 243 LBC gas gun on a 24” BHW barrel (cheap and easy). Playing with 103 ELD’s and 8208 so far. Simple neck down, no fire-forming. Disgustingly fun little round - I had lusted after a 6mm Grendel variant for a couple of years, but didn’t care to jump whole hog into a single source cartridge. Now, looking back, I already wish I hadn’t waited so long to put one together. Strongly considering doing one on a Howa or CZ mini action for my 6yr old son.
     
  19. baddog

    baddog Silver $$ Contributor

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    I picked up a barrel from

    https://www.ar15performance.com/inc/sdetail/38016/61304

    It is their form of a 6mmAR . That was quite a few years ago , it seems they went to 3R rifling since . I believe mine was 6 groove , all the rest looks to be the same . It is very accurate and I find Lapua brass works best for me in forming the case . I use a Redding S die for the Grendel 6.5 and just change out the bushing and expander button. Mine really like 87 Berger VLD hunting bullets and 85 gr Sierra HPBT bullets . Varget and IMR 8208 XBR both work well . Great cartridge it does out shoot my current 6.5 Grendel .
     
  20. gunsandgunsmithing

    gunsandgunsmithing The best tuners and wind flags on the market Gold $$ Contributor

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    A 6 Grendel is a ppc with a little boost. Like a ppc, it shines in a bolt gun.
     
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