Load testing with new brass

Discussion in 'Reloading' started by BML, Jul 1, 2012.

  1. BML

    BML Well-Known Member

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    Had to scrap all my old brass but I'm still developing my load. I'm prepping 40 new pieces of Norma brass as we speak and got to thinking. I just assumed I would have to fire form every piece before I could resume testing. Am I right or can I test with new unfired brass?
     
  2. RockyMtnMT

    RockyMtnMT Official LRH Sponsor

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    If you are not shooting some sort of a wildcat and you full length size you should be fine.

    Steve
     

  3. BML

    BML Well-Known Member

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    Shooting a savage 6.5x284. I didn't FL size this new brass but I did neck size. I usually wait until I get a stiff bolt before I FL size.
     
  4. RockyMtnMT

    RockyMtnMT Official LRH Sponsor

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    I always full length size from brand new and there after. That way nothing can go wrong. I still think you will be fine. I think it would be a good idea to full length brand new that way you will not have any chambering problems. Then go back to your neck sizing practice after that.

    Steve
     
  5. rscott5028

    rscott5028 Well-Known Member

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    I always like to know what my loads will do with new brass as compared to fired brass. If you've found an accuracy node, then the MV may be off a hair, but your accuracy shouldn't completely deteriorate.

    NK vs FL sizing will also affect the comparison for a given load.

    My main focus is normally concentrated on fired bass that's fully prepped regardless of whether I'm NK or FL sizing for that cartridge. I see no reason to waste barrel life fireforming just for the sake of it. ...might as well practice and collect useful data.

    -- richard
     
  6. MNbogboy

    MNbogboy Well-Known Member

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    I agree with Richard that if you have found something promising that you probably should work from there....Obviously with any component change, ( being a new lot of brass, new lot of powder or even bullet or primer changes), caution should be taken with the new load...If your new brass is of different manufacture than your old brass you may see quite a bit of difference in velocities and pressure signs...

    As far as FL vs NK this will be a forever ongoing debate....I have found that FL often creates the best consistency but when I neck size I check every case in the chamber after sizing and bump accordingly to prevent any stiff closings....

    Randy
     
  7. BML

    BML Well-Known Member

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    Thanks for the tips fellas. I appreciate it.
     
  8. Mikecr

    Mikecr Well-Known Member

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    New & sized brass is not the same as fireformed & sized brass.
    I say 40 extra shots here could save you more than 40.
     
  9. BML

    BML Well-Known Member

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    Im curious to know if anyone who has already developed a load has shot brand new brass and compared the results to that of fire formed brass.

    What were the differences in groups, poi, velocity etc?

    At this point I'm leaning towards loading as if I were testing.
     
  10. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    I never much care in the rounds I use.
    The 6.5x284 is a bit smaller, but it shouldn't make more than a few fps difference and unless your chamber is huge it should make little difference in accuracy.
    I routinely use whatever brass I have for test loads, as long as it is all sized, trimmed, and at the same number of firings.
    It's not like the case only expands to fill the chamber only after the first firing.
     
  11. MNbogboy

    MNbogboy Well-Known Member

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    It is almost certain you will see a difference in POI, velocity and most likely accuracy also.....But this information can all be applied as future reference as your load developement progresses....

    As Mikecr implies the fireforming process is very essential to any load development....Personally I believe the cases are not fully stabilized till at least two firings....But most likely you may be able to "weed out" some obvious undesirable results during the fireforming process with the first 40 firings....Testing for seating depth is one for instance.....

    My opinion is don't waste those first 40 shots just to "season" the case...Any info you record may come in handy later on down the road..

    Randy
     
  12. Tumbleweed

    Tumbleweed Well-Known Member

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    I discovered last year that there was a huge difference in my rifle between new brass and once fired, resized brass. This was NC brass. With the new, I chronographed the load at 3,040 fps. With the same load using once fired, FL resized brass velocity is 3,120fps. Accuracy, velocity and ES are all better with the once fired.
     
  13. BML

    BML Well-Known Member

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    Re: Load testing with new brass-Pic and results added

    Well I had plans to test 5 different loads today, but was interrupted by some much needed rain.

    A couple weeks ago I tested a load on brass that had been fired 14 times. That 3 shot test shot an impressive .354. I knew I was getting close to the end of that brass life, but wanted to test a 12 shot group with that same load to get a good batch of data. The first 8 shots were all over the place. Then I split a case on the 9th shot so I called it quits.

    Fast forward to today. First three shot group with brand new unfired brass, same load as the .354 group from a couple weeks ago, shot .451


    [​IMG]

    I was able to test just one more load before the rain started. Same seating depth, but .010g less powder. This is brand new load so I don't have anything to compare it to. Shot a decent .555.



    Now I know 3 shots represent a very small sample of how brand new brass performs against fire formed brass, but it's a start anyway.
     
  14. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    I'm already at .3moa( 3-3shot groups separate days) with my 7stw with new rp brass using the 171 matchburner and rl25. An 8# 7stw shot off sand isn't going to get much better with fired brass.