Page 1 of 6 1 2 3 4 5 ... LastLast
Results 1 to 10 of 52
  1. #1
    Grandmaster shibumiseeker's Avatar
    Join Date
    Nov 2009
    Location
    near Bedford on a whole lot of land.
    Posts
    8,649

    New brass life test: annealing

    Countryboy19 and I are conducting a brass life test to gather some data to answer the question: does annealing extend brass life?

    This is a question I've wanted the answer to for a long time. There's good reasons to anneal, but I've yet to see hard data on case life. We discussed this in a previous thread:
    http://ingunowners.com/forums/ammuni...ife_or_no.html

    As folks know, I like empirical data rather than wild speculations (even SWAGs), and since my shooting building and range allow me to load, turn around and shoot, and load again, I've conducted a number of these tests over the years and my conclusion is that people often aren't using their brass to the full potential.

    So after much discussion, CountryBoy19 and I had decided that at least for our first rounds of testing, we're going to fire to failure 5 pieces of brass with no annealing and neck sizing. Then 5 with annealing every so often to be determined by how long the brass in the first round lasts, with neck sizing only. Then 5 no annealing but with full length resizing, and then 5 rounds with annealing every few cycles to be determined by how long the brass lasts with full length resizing. Where we go after this will be determined by what we find with this initial test.

    Some limitations: A sample size of 5 is on the very edge of statistical usefulness. It is enough though to get us a first order approximation. Depending on what we find we may increase the sample size if we feel the need, but we're going to let the study guide where we go.

    The gun used: A Remington 700 .308, 20"bbl (I think, CB19, is this correct?)

    Dies are Lee .308
    Press is Lee Turret
    Brass is Remington brass of a similar lot, once fired factory ammo fired from this gun.
    Primers are Wolf Large Rifle
    Powder is 46.1gr of Varget thrown with a Lee Autodisk Powder measure (as much as .5gr variation is typical)
    Bullets are Remington 165gr PSP Core-Lokt

    No crimp.

    We chronyed an average velocity of 2425fps.

    Brass starting length was 1.99" appr. and recommended trim to length is 2.005.

    This time we got in 30 cycles before we ran out of time.

    We fired 18 cycles before noticing a very small split on a case mouth, about .5mm, so we figured it'd be out of the running soon. Well, it took several more firings before it got a little wider, but it is STILL in the running as it hasn't grown much.

    At load 25 two of the pieces of brass were starting to get hard to chamber so we did one full length resizing of the entire lot. Measuring after FL sizing the brass was about 1.995".

    All 5 pieces are still in the running. We'll be resuming the test in a couple weeks when more bullets come in and our schedules coincide.

    CountryBoy19, anything I left out, or you want to add?
    Last edited by shibumiseeker; 05-15-2011 at 20:51.
    IWTFM Eternal vigilance is the price of chickens. JFC advocate.

  2. #2
    Grandmaster
    Join Date
    Nov 2008
    Location
    Bedford, IN
    Posts
    6,529
    Quote Originally Posted by shibumiseeker View Post
    I think, CB19, is this correct?

    CountryBoy19, anything I left out, or you want to add?
    Correct, Remington 700 Tac (20" bull barrel).

    I can't think of anything to add right now. It's going to be interesting to see how long these cases last with no annealing. The cracked one already surprised me by how long it's lasted (I figured once the crack started it would go downhill fast).

  3. #3
    Leo
    Leo is offline
    Master
    Join Date
    Mar 2011
    Location
    Lafayette, IN
    Posts
    4,323
    Cool test. Thanks for posting. The only brass that I ever anealed was to make 7mmTCU brass out of .223. That was so it didn't crack during forming, I never though about using it for making brass last longer. Are the primer pockets getting loose?

  4. #4
    Grandmaster shibumiseeker's Avatar
    Join Date
    Nov 2009
    Location
    near Bedford on a whole lot of land.
    Posts
    8,649
    Quote Originally Posted by Leo View Post
    Cool test. Thanks for posting. The only brass that I ever anealed was to make 7mmTCU brass out of .223. That was so it didn't crack during forming, I never though about using it for making brass last longer. Are the primer pockets getting loose?
    I've actually never had primer pockets get loose on these tests. That probably has a lot to do with the fact that I'm usually do them with middle power loads.
    IWTFM Eternal vigilance is the price of chickens. JFC advocate.

  5. #5
    Grandmaster shibumiseeker's Avatar
    Join Date
    Nov 2009
    Location
    near Bedford on a whole lot of land.
    Posts
    8,649
    After a hiatus to allow our busy schedules to mesh, we met again to resume the testing Saturday.

    We got 40 more loadings for a total of 70, before we ran out of time again.

    The one piece of brass that has a small neck split at #18 surprised us. It wasn't until loading #40 that we noticed it start growing. At firing #61 we finally took it out of service after the neck had completely split and the split was working its way down the shoulder. Our criteria for failing the brass was when it would no longer hold enough bullet tension to resist being pushed in by hand after sizing.

    A second piece of brass had a small split starting near the case shoulder at firing #61 and by #70 it had doubled in sized but is still in service.

    First brass split about double it's initial size somewhere around loading #50:



    Final length when we failed it:



    Second piece split after firing #70, about double initial size:

    Last edited by shibumiseeker; 05-15-2011 at 17:08.
    IWTFM Eternal vigilance is the price of chickens. JFC advocate.

  6. #6
    Leo
    Leo is offline
    Master
    Join Date
    Mar 2011
    Location
    Lafayette, IN
    Posts
    4,323
    Wow, I never would have guessed rifle brass would hold up that long. Good job on testing and documenting the test. Thanks for sharing.

  7. #7
    Grandmaster
    Join Date
    Nov 2008
    Location
    Bedford, IN
    Posts
    6,529
    Quote Originally Posted by Leo View Post
    Wow, I never would have guessed rifle brass would hold up that long. Good job on testing and documenting the test. Thanks for sharing.
    Remember that we're neck-sizing only, and we're only sizing it just enough to maintain good neck tension. Really the only part of the brass that is being worked is the neck, and it is being worked as little as possible.

    If you full length size brass it probably won't last this long.

    We have discussed further tests involving this, like testing the same thing by full-length sizing so we may get an answer to that eventually. It's just a matter of time. Shibumiseeker and I both have very busy schedules and it's tough to find a time that we're both available to go out and shoot.

  8. #8
    Expert Yeah's Avatar
    Join Date
    Dec 2009
    Location
    Ekwok,AK/Paragon,IN
    Posts
    2,155
    Quote Originally Posted by CountryBoy19 View Post
    Remember that we're neck-sizing only, and we're only sizing it just enough to maintain good neck tension. Really the only part of the brass that is being worked is the neck, and it is being worked as little as possible.

    If you full length size brass it probably won't last this long.
    The pro annealing crowd and the pro FL sizing crowd has a lot of crossover.

    I did a similar test a few years ago when I went click-clack crazy for a short time and more or less had to FL size. Annealing still didn't 'pay' once I factored in the time spent at the annealing bench rather than shooting.
    Playing the preference points game...

  9. #9
    Marksman ruger1800's Avatar
    Join Date
    Apr 2010
    Location
    In a spydy hole
    Posts
    697
    Are you anealing these 5 case after each firing? how much have you trimed off total up to the 70th loading? Also what are you seating the primers with. hand primer or press.

  10. #10
    Grandmaster
    Join Date
    Nov 2008
    Location
    Bedford, IN
    Posts
    6,529
    Quote Originally Posted by ruger1800 View Post
    Are you anealing these 5 case after each firing? how much have you trimed off total up to the 70th loading? Also what are you seating the primers with. hand primer or press.
    No annealing, this is the control batch. No trimming, the cases haven't grown because we're neck-sizing. Seating the primers with a press.

Page 1 of 6 1 2 3 4 5 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •