Grinch

Discussion in '6mm, 6.5mm, and .25 Cal (Not 6BR)' started by grovey, Nov 9, 2019.

  1. grovey

    grovey

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    Anyone still shooting the 6mm Grinch? Do they have enough ass to use a 8 twist with 105 class match bullets to score shoot out to 400-500 yds and be competitive , or are they best suited for a 10 or 12 twist and 80's?
     
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  2. dbduff

    dbduff Gold $$ Contributor

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    Shooting 108's at 2850, no pressure signs. 30 in Krieger 7.5 twist.
     
  3. BartsBullets

    BartsBullets Gold $$ Contributor

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    Grinch with 103-105 gr bullet with 8 twist barrel at 2900-2920 will shoot with anything out there!

    Bart
     
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  4. Mulligan

    Mulligan Gold $$ Contributor

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    Bart,
    Looking at match reports and studying threads on this forum, it appears you are currently shooting a BRA. What lured you away from the Grench?
    I am pondering a Grench for one of my grand girls to shoot using my PPC rig. I do not want to handicap them, but if the old guy and get by without buying another rifle to get the girl in the shooting sports I might as well save the coin for bullets.

    CW
     
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  5. BartsBullets

    BartsBullets Gold $$ Contributor

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    At one point I was reloading and testing for 6 Dasher, 6BR, 6ppc, 6ppc improved, 6 Grinch, 6 Grendel and 6 BRA! So to keep from running myself ragged I narrowed it down to just the 6ppc and 6BRA.

    The Grinch is a great cartridge. It’s every bit as accurate as anything out there. It’s easy to tune but making the brass was a bit of a PITA! I was running a .268 and had to turn necks. If I did it again I’d make it a no turn.

    I gave the 6BRA try. It was just as accurate as the Grinch, brass was easier to make, and it had another gear the Grinch didn’t have. So that’s why I started shooting the 6BRA.

    BART
     
  6. Mulligan

    Mulligan Gold $$ Contributor

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    Thanks Bart,
    That is exactly the information I was looking for.
    CW
     
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  7. gunsandgunsmithing

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

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    At your stated yardages, I'd do a 8 or 10 twist straight 6 Grendel and try 90 Bergers or similar. Itll be a tough to beat combination.
     
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  8. Mulligan

    Mulligan Gold $$ Contributor

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    What about 600 BR?
    CW
     
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  9. gunsandgunsmithing

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

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    I think it will depend on conditions more than anything but run the numbers on that 90 Berger bt vs say a 105. If conditions are good to fair, I think it will surprise you. If conditions are tough, the bigger guns seem to rise up on those days.
    That 90 is easy to tune and has good speed. The bc difference of a 105 doesn't seem to show up as much as you'd think until you get to about 800 or so.
    With an 8 twist, you can try both against one another and judge for yourself. I can push the 90's around 3,100fps, fwiw.
     
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  10. Mulligan

    Mulligan Gold $$ Contributor

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    That's impressive.

    I checked, I can put 30.5gr of H4895 in a ppc case and have room for a heavy bullet. The Grench is .08" longer at the shoulder, correct?

    CW
     
  11. gunsandgunsmithing

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

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    I'm more familiar with specs on a straight 6 Grendel than the grinch. A 6 Grendel is precisely a .070 long ppc.
    I debated doing a grinch but not enough difference to justify fireforming and custom dies, imo. Flip a coin, performance wise.
     
  12. WyleWD

    WyleWD Silver $$ Contributor

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    There are a couple of older threads where maybe Bart and some others have shot some 500-600yd targets with the Grinch and or the Grendel. This might be one of those threads: http://forum.accurateshooter.com/threads/6mm-grinch.3911719/

    I've seen a few 1 inch and lower groups at 400yds with the 80's to comfortably say that in capable hands the cartridge could do quite well with the 90-103 gr bullets.

    The .268 neck 6 Grendel is relatively easy to make and there is now lower priced 6.5 Grendel brass available to experiment with and train on if you're not intimately familiar with necking down, turning, etc. I like it!. JME WD
     
    Last edited: Mar 21, 2020
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  13. gunsandgunsmithing

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

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    Me too WD, and that's been my experience with it. The 80's shoot well but don't have enough of a bc edge over the light bullets to justify, unless yours really likes them a lot. But the 90-95 range bullets have a significant bc edge over the lights and can flat shoot. The case handles pressure very well and is very accurate. IOW, you can push it hard to get up there where it likes it and doesn't leave much if any speed on the table vs a BR. I think the 90 grain class of bullets get over looked a bit, being sort of a "tweener" weight. Just run the numbers and give them a try if it sounds like something you might like. It's very easy to tune and shoot ..and I think it can run with anything out to 600 yards. After that, I'd lean toward a little more horsepower. Just my 2 cents though.
     
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  14. BOB LEE SWAGGER

    BOB LEE SWAGGER

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    Is it just a matter of necking down to 6mm and you are good to go?
     
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  15. gunsandgunsmithing

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

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    Yep, with a straight Grendel, that's it. Of course, if you're running a tight neck you'll need to turn, like anything else.
     
  16. BOB LEE SWAGGER

    BOB LEE SWAGGER

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    Thank you. Thankful there is no internal/donut issues. So...spec a grendel with a 6mm neck - seems WAY easier than a grinch!
     
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  17. gunsandgunsmithing

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

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    I can pm you you my print. I use off the shelf redding Grendel bushing dies with it. Just drop in the right bushing for you brass thickness. Annddd...I use a 6PPC seater die. How much simpler can it get?:)

    edit...print in next post
     
    Last edited: Mar 30, 2020
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  18. gunsandgunsmithing

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

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    He called it a 6 Major on the print but same thing. It'll take at least .274 for a no turn and the .070 freebore is long enough to work with 68-80 grain bullets. I'd go a little longer for heavies and a little shorter for lights but the .070 is a good compromise that works with a pretty wide range of bullet weights.

    All that said, Redding changed their die dimensions a little after I had this reamer made. I'd make it .0005 smaller at both the shoulder and the .200 line if I were doing it now...But no big deal as is.
     

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