Am i doing something wrong?

Discussion in 'Reloading' started by Blacktail, Oct 5, 2008.

  1. Blacktail

    Blacktail Well-Known Member

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    I have been loading for my 7 mm STW for about 2 years now and have had decent success with the 140 accubond, 140 tsx and the 160 accubond. All around 3/4". The 160's the first time out i used 79grains of H-1000 and got the gun to group under 1/4" at 3212 fps I thought finally found my load. Went home loaded up 20 not changing a thing. The last to times i have gone out to check zero for a trip and could do any better than a hair over 3/4" I havent changed anything i am aware of. What the heck am i doing wrong?
     
  2. shootinfool

    shootinfool Well-Known Member

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    I have found that this has happened to me in the past. It is indeed very frustrating. I have found that more often than not mine was caused by a difference in temp. I don't know if this is the reason why, but that is the only variable(that I am aware of) that changed from one firing to the next. I have found that I have even loaded 50 or so at one time and went out and one day they shoot .3-.4 and then a couple of weeks later, they shoot .8-.9. same load, loaded at the same time, same set up and everything.
     

  3. boomtube

    boomtube Well-Known Member

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    "... got the gun to group under 1/4" at 3212 fps I thought finally found my load. Went home loaded up 20 not changing a thing. The last to times i have gone out to check zero for a trip and could do any better than a hair over 3/4" I havent changed anything i am aware of."

    Doubt you are doing anything "wrong", you just fired more rounds and have gotten a more true picture of what your rifle and loads are capable of doing on a regular basis.

    The 1/4" groups would make you competetive in a formal Bench Rest match against rifles with custom actions and triggers with expensive custom barrels while firing custom bullets and using 36X scopes. Doubt your STW is capable of that except for an occasional random group. And I KNOW no hunting bullet is consistantly capabile of that kind of grouping.

    I think your 3/4" accuracy is really GREAT for a truly high powered hunting rifle and ammo! Smile a lot and don't worry about it.
     
  4. Blacktail

    Blacktail Well-Known Member

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    Thank you i was kind of thinking that. You helped put my mind at ease.
     
  5. ol mike

    ol mike Well-Known Member

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    --------------------------------------------------------------------------------------
    Had i wrote a reply sooner it would have said ^^^^ these same words.

    This has been very irritating to me also ! right up there w/ my rifles changing point of impact..Top quality stocks-rings-scopes -barrel ---still nothing works the same day in day out.
    I pondered it all many many times and am at a loss w/ both.

    It's like Joe Dirt's dad says how does a posi-track in a hemi work --it just does--..
     
    Last edited: Oct 7, 2008
  6. Loner

    Loner Well-Known Member

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    Look for the most forgiving load in your ladder testing, not always the tightest group.
    Everyone goes through the results you described at one time or another with normal
    or light barreled guns.
     
  7. bruce_ventura

    bruce_ventura Well-Known Member

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    This is why I shoot 5-shot groups. They're bigger than 3-shot groups, but also more consistent. For hunting rifles, I shoot the group over a 60-minute span. If I had the time, I would shoot 10-shot groups.

    Sounds like your 7 mm STW is a good shooter, even at 3/4". FWIW, I only have one or two rifles that can produce groups smaller than that. Below 0.5", my technique is the limiting factor, so I'm not sure how well they really can shoot.
     
  8. dig

    dig Well-Known Member

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    This can be frustrating I know. I have this happen in our Arizona temperatures and believe a lot of it is environmental conditions, Temp, Humidity, Pressure etc. . . I have a .300 that clover leafs when over 85 then opens up in cooler temps. I don't hunt much in 85 degree temps. Also check your groups at longer distance they probably hold same MOA (don't get worse/stabilize) A lot of good advice was given 1) 3/4 MOA in a high power/magnum is sufficient, even good for long range 2) try different powders, the IMR/H brands have been much less sensitive for me 4831sc and 4064 specifically. 3) I went to the OCW (Optimal Charge Weight) method for developing hunting loads, google it. This method has produced more consistent results at long distance with less shift in impact which is what I am looking for. Sometime the tiniest groups DO NOT translate into the best long range load for all conditions. Sounds like you are doing fine. This is what keeps us buying products and people inventing right!