Virgin brass vs. fire formed

Discussion in 'Reloading' started by KQguy, Mar 1, 2009.

  1. KQguy

    KQguy Well-Known Member

    Messages:
    322
    Joined:
    Dec 7, 2007
  2. Supertrucker

    Supertrucker Well-Known Member

    Messages:
    140
    Joined:
    Feb 4, 2009
    Not sure what this test really accomplished? I don't know of anyone, with the exception of fireforming for ackley cartridges that fireforms standard cartridges. What I and I'm sure most other people do is use virgin brass and test loads and then use those fired cases.
     

  3. KQguy

    KQguy Well-Known Member

    Messages:
    322
    Joined:
    Dec 7, 2007
    I was alway's under the impression that virgin brass shot alot different than fired brass,because of the interior case capacity changing.
     
  4. johnnyk

    johnnyk Well-Known Member

    Messages:
    1,731
    Joined:
    Dec 24, 2001
    Accuracy wise, I have never really been able to tell any difference. I prep V brass just as I would fired brass but note it in my journal that it's V brass.
    When I first started reloading 25 years ago, I read that accuracy wasn't as good with V brass as it would be with subsequent firings. I got in the habit of denoting V brass in my journal but never the firings afterwards with the same brass (i.e., 1st,2nd,3rd,etc.). Don't know why, guess it was my "mulligan" in case the groups were crappy. I hate those kind cause in the back of my mind I know I should try them over with fire-formed brass, just to see! OCD?
    I have had some mighty fine groups using V brass in every caliber I have reloaded for. Some have been repeatable, some haven't. In my mind it holds about as much water as the full length vs. neck sizing theory! Who really knows? Just load, shoot and reload some more to get your "group therapy". lol. JohnnyK.
     
  5. boomtube

    boomtube Well-Known Member

    Messages:
    1,595
    Joined:
    Oct 8, 2007
    "I was alway's under the impression that virgin brass shot alot different than fired brass,because of the interior case capacity changing."

    I've read that "serious expert" pronouncement too. Always make me wonder if the writer had ever actually done it. If average accuracy changes between virgin brass and four times fired, I can't prove it.

    I figured the chamber pressure was quite enough to move the "tight" brass case into a precise fit within the chamber very well, and pretty fast too! :D
     
  6. friendlyfireisnt

    friendlyfireisnt Active Member

    Messages:
    33
    Joined:
    May 5, 2006
    I haven't seen a difference in accuracy, but I did notice a difference in POI on target by about 1" between virgin and fired brass.
     
  7. boomtube

    boomtube Well-Known Member

    Messages:
    1,595
    Joined:
    Oct 8, 2007
    "... I did notice a difference in POI on target by about 1" between virgin and fired brass."

    Sure wouldn't ever say anything CAN'T happen, it just hasn't happened to me. At what range did that 1" impact shift occur?
     
  8. friendlyfireisnt

    friendlyfireisnt Active Member

    Messages:
    33
    Joined:
    May 5, 2006
    I first discovered it at 100 yards, and it was consistent. One lot of brass, I shot some once fired next to virgin brass, and the POI was 1" off. Can't remember if it was high, or low, but it was almost exactly 1" off vertically on multiple range trips.
     
  9. boomtube

    boomtube Well-Known Member

    Messages:
    1,595
    Joined:
    Oct 8, 2007

    Interesting. What did it do after being reloaded? (If you've gotten that far.) I mean, wonder if it will stay there or move back to your old zero. ??
     
  10. friendlyfireisnt

    friendlyfireisnt Active Member

    Messages:
    33
    Joined:
    May 5, 2006
    That's what I was saying.

    With my Vanguard .30-06, I did load development with virgin Winchester cases (175gr SMK, H4350, WLR primers).

    I then confirmed my load using the once fired brass, and some more of the virgin brass. POI was 1" different vertically. I confirmed it while finishing off the virgin brass, side by side with once fired brass.

    It has maintained the same POI through the rest of the firings. Only the virgin brass had a different POI.
     
  11. phorwath

    phorwath Well-Known Member

    Messages:
    4,896
    Joined:
    Apr 4, 2005
    No worries then, provided you're content with 10" of vertical shift @1000 yds. :rolleyes:

    I never use unfired brass for long range hunting. I've commonly measured much higher case neck and bullet runout in virgin brass compared to brass that's been fireformed to my chambers. Which in itself was enough evidence for me to fireform prior to preparing for, and taking, 700+ yard shots on game. If you're shooting 3-400 yds or less on big game, I agree the mission can be accomplished with factory ammo. Not too difficult to hit a 10" diameter kill zone at 350 yds. When I'm planning on stretching it out to and beyond 1000 yds, I'm not willing to cross my fingers and hope it doesn't matter. And I'm not willing to waste the time, components, and money in order to prove that it doesn't matter. I find it simpler to just use brass that's been fireformed in my rifle chambers.

    I rather doubt that benchrest competitors use unfired virgin brass during 1000 yd competition. I'm sure some forum member that hunts also competes or at least knows about 1000 yd match competition. Maybe they'll chime in and tell us if the competition crowd competes with unfired virgin brass. If they do, maybe I'll change my mind. If they don't, no one will change my mind with their backyard rule-of-thumb experiences.
     
  12. KQguy

    KQguy Well-Known Member

    Messages:
    322
    Joined:
    Dec 7, 2007
    I agree,I would not shoot long range with virgin brass.But I will load develope with it.I don't want to waste barrel life by firing off hundreds of rounds at rocks just to fire form my cases.I figure by the time I develope a load,most of my brass will be fired,and if there is a slight difference with the fired cases,I can adjust the load a little bit to make up for it.If there are some virgin brass left over that never got shot through the load developement process,I will just save them for shorter range stuff(100-400 yds.).I think barrel life is too short to be wasting shots to fireform.That's just my opinion.:)
     
  13. davewilson

    davewilson Well-Known Member

    Messages:
    2,634
    Joined:
    Feb 19, 2004
    can't say i've seen any differnce between new and fired brass with my edge. accuracy, POI, ES, velocity all seem to be the same.of course i FL size every time and to be honest, my best groups are from unfired brass. 2 yrs ago Jason Baney won the World Open i think they call it up at the Williamsport 1K shoot with new brass. he didn't even do ANY prep work on it. not saying this is what he normally does, but it's what he did that day.
     
  14. Frogman77

    Frogman77 Well-Known Member

    Messages:
    154
    Joined:
    Feb 1, 2009
    I'm fairly new to the game but I have found a huge difference between new winchester brass to fire formed brass in my .30-06.

    I did some measurements of virgin brass and once fired brass and the new brass at the shoulder measured .0195 - .020" short of my once fired brass. Accuracy was about 1.25 moa at 100 yards with virgin brass and in the .3 moa range with once fired brass.

    I am guessing this is due to the excessive headspace with the virgin brass.

    My once fired brass measures .005" longer at the shoulder than book specs. (1.953" once fired vs. 1.948") This is a snug fit in the chamber and requires just a little more effort to close the bolt. New winchester brass measures 1.933-1.934" to the shoulder

    I need to try some different brass to see if they measure that short when they're new. I can do ladder testing with new brass but I'm not sure load development for accuracy will work. At least with new winchester brass measuring that short in my chamber.