never found it.

Discussion in '7mm STW' started by lif2fsh, Jul 7, 2013.

  1. lif2fsh

    lif2fsh Member

    Messages:
    21
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    Jun 13, 2007
    Never found that magic pill that shoots 1/2 moa from my STW. Can't say I didn't try. Have been looking through my records beginning in 2003 and here are the different component's and some of variation's of them.

    Powers:H4831sc IMR4831 IMR4350 H1000 IMR7828 IMR7828SSC RETUMBO
    Cases: r-p
    Primers: FEDERAL..CCI
    Bullet's: Sierra 160 & 150 HPBT 120 SPT
    Nosler 140 & 160 ACCUBOND & PARTION.
    Loads were started just over minimum published and worked up until pressure signs or groups open up. Played with length of 3.600 down to 3.550. 3.600 being max for my mag. The gum is a Winchester mod 70 in SS. floated barrel, glass bedded with a Leupold 3x9. And the nut behind the trigger is a fair shot. I use this gun for all my big game hunting and have had great success, just would like to see some better groups.

    My best is.. Nosler 140 AB over 74.5 of 7828 produces ABOUT .5 to .75. 3 shot groups.@ 100yds.
    that's as good as it gets?

    Thanks,
    Mike.
     
  2. SnakeRiverEric

    SnakeRiverEric Active Member

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    Apr 30, 2013
    What speed did you get with that gun, which is same gun I have. Mine likes R22 78gr/R25 80gr, likes both 140 and 160 AB's, get 3400ish with 140's, and 3240 with 160's. Accuracy is 3/4" to 1.5".
     

  3. bkondeff

    bkondeff Well-Known Member

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    Feb 2, 2008
    I was just going to post a question about velocity, which you just answered.

    Have a 26" barrel, shooting 80.0 gr H1000 with F215, OAL 3.60 and got about .9" at 100 yards at 3260fps. No pressure signs despite 84 deg tems(kept loaded rounds about 80 deg). I was wondering if this was unusual.

    Will back down a bit and try .5 grain loads from 79.0 until I find pressure, which can't be far off from 80.0 grains? Not sure I can get much more OAL from my magazine, do you think a primer change could help much? Would like to get .5-.7" and then see how it shoot farther out.
     
  4. lif2fsh

    lif2fsh Member

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    Jun 13, 2007
    SnakeRiverEric,

    Speeds are a little under what you got, 160 were about 3050 and 140 about3250.
    I just don't think the Accuracy is as good as it should be.
     
  5. walter351

    walter351 Well-Known Member

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    Sep 16, 2008
    Try shooting a barnes bullet. My accuracy increased greatly once I started to play with barnes bullets.
     
  6. Lefty7mmstw

    Lefty7mmstw Well-Known Member

    Messages:
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    May 13, 2012
    The barnes has been great for my 375; but my 7 stw's have really liked 140 grain sierra pro hunters or 140 grain accubonds.
    The screwy thing is either stw (my 9" twist sendero or my 10" twist custom bbl.) hasn't liked heavy pills that well. The 7 rem's and 7 rum I've had seem to do better there. Likely just barrel preference as others like mudrunner are doing well with heavy bullets in their stw's. Try a different weight of pill before you give up on her.
     
  7. MudRunner2005

    MudRunner2005 Well-Known Member

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    Oct 13, 2008
    Like Lefty said, I have been having some good luck with the 180's out of my 9.25" twist factory Sendero SF barrel. And barrel prefence has alot to do with it. You will just have to play around with different bullet brands, models, and weights to figure out what your barrel prefers.

    For example, my rifle isn't a big fan of the 160 Sierra GameKings (1 MOA @ 100 yards), but I had to shoot them for years and years before I started reloading, because that was the best bullet offered in the Federal Premium line for the 7mmSTW (never liked Winchester or Rem ammo, from bad past experiences). Then Federal started producing STW ammo with the 160 Nosler Accubond bullets. I switched to those, because my groups increased substantially, going from 1 MOA with the Sierras to 1/2 MOA with the Accubonds. Both bullets were same weight, same powder, same brass, same brand, and loaded at the same factory. But my barrel preferred one over the other.

    If your rifle is liking the 140's but not the 180's, try an intermediate pill, such as the Berger 168 VLD. Seems lately that my STW has been preferring them to the 180's, which is odd, how it shot so well before when it was cool outside with the same load of H1000, but now that it's hot outside, that group will shoot good, but inconsistantly. They claim H1000 to not be temp sensative, but in my recent experiences I've found it to be.

    I'll have to do more testing before I can make a final conclusion, since 1 incident is more likely a fluke, than it is evidence towards a trend.