? 0n .243/.308 reloading

Discussion in 'The Ammo & Reloading Forum' started by jbmid1, Jul 7, 2012.

  1. jbmid1

    jbmid1 Well-Known Member

    Feb 3, 2011
    Tucson, AZ
    I know it's possible to use make .243 from .308 and vice-versa. How
    highly recommended is it. Anybody here done this either way. If so, which is easier, necking .243 up, or .308 down?
  2. JLA

    JLA Well-Known Member

    Feb 26, 2007
    Heart Of Texas
    Its doable but not practical. necking down a .308 will make a really ugly neck. and necking up a .243 makes a really thin one. Both cartridges are readily available and easy to get.

  3. 76Highboy

    76Highboy Well-Known Member

    Jan 1, 2012
    I think I am right when I say you can take the .308 down to .243 or visa versa. However I prefer not to because if you take .308 to .243 it is still head stamped .308. Therefore you have room for error and a big accident. Can you trade your .308 with someone that has .243? I would try to avoid it if it were me but that is just my preference.

    I hope that helps.
    Last edited: Jul 8, 2012
  4. JLA

    JLA Well-Known Member

    Feb 26, 2007
    Heart Of Texas
    you cant just simply run a .308 into a .243 die and get a .243 case. It is such a drastic reduction in neck diameter it has to be done in steps. You get a big wrinkle in the middle of the shoulder doing it this way. i was bored one afternoon and tried it..You can however, run a .243 case into a .308 die and get a .308 case so long as the neck doesnt split. this is where annealing plays a big part of the process.
  5. cpttango30

    cpttango30 Guest

    I am glad I didn't know this when I necked down 500 308s by running them up into a 243.

    You should anneal before and trim after. If you do that it is just that easy as running 308 brass into a 243 die. Going from 243 up to 308 is a very bad idea as you will end up splitting necks very quickly.

    As for making 308 out of 30-06 brass that's crazy because you would have to Cut the brass down then form it in steps annealing between steps then trim it again then you would need to inside and outside neck turn the brass.
  6. aa1911

    aa1911 Well-Known Member

    Dec 12, 2010
    Pacific Northwest
    as said above, both very common rounds, I would not even consider doing either, just trade 'em. The time you spend attempting such a big change will likely be lost in far fewer reloads from them not to mention the % of ruined cases.

    just my .02
  7. JLA

    JLA Well-Known Member

    Feb 26, 2007
    Heart Of Texas
    Id like to see some pics of that Tango. Ive tried it. The problem is the .243 has twice the shoulder and half the neck length of a .308. you can do it, but how do you get rid of the wrinkle?
  8. cpttango30

    cpttango30 Guest

    Never had any wrinkles in my brass. Just sized them and trimmed them and loaded them.

    How hard is it to see a difference in a .243" neck and a .308" neck? If you can't see that maybe you shouldn't be reloading to begin with.

    What I would do is use Remington brass for one and Winchester brass for the other. You can also mark the cases with sharpie 3 lines on the case body for 308 2 lines for 243.
  9. gdmoody

    gdmoody Moderator Supporting Member

    Sep 7, 2007
    Athens, Georgia
    I don't have a .243 so I have never tried either. I have taken .270 brass and resized it into a 30-06, just to see it done. I have only done a couple, like I said just to see it. Those two are still loaded up somewhere in my stock-pile.
  10. JLA

    JLA Well-Known Member

    Feb 26, 2007
    Heart Of Texas
    Heres what i recommend then.. I will take a handful of .308 cases and make .243s from them and take pics and post them here. You do the same, and we will both only use a .243 FL DIE. Of course annealing is allowed. Im curious to see if we get the same results. Unless youre performing a step youre not mentioning i cant see it not having a deformed shoulder. Ive tried it repeatedly just for giggles.

    And ill ignore the snide comments in your second paragraph for now.. It is not my intention to gain your approval as to whether or not i am qualified to reload.
  11. JLA

    JLA Well-Known Member

    Feb 26, 2007
    Heart Of Texas
    Just did 5, and to make sure it was clear I set the cam on Macro. Note the wrinkle in the shouler of the 'formed' .243 cases that is precisely where the base of the .308 neck was.. My fear here, is a separation resulting in a hard to remove neck portion stuck in your chamber... Will it iron out during fireforming? Maybe.. probably.. but again the .308 and the .243 are both readily available and very common so my argument goes back to WHY BOTHER, other than just for giggles.

    Note on the brass.. Both the .243s pictured and the 5 .308s pictured are Hornady match brass fired in match chambers and have been annealed and trimmed on every cycle since new.

    Your turn Tango..

    Attached Files:

  12. cpttango30

    cpttango30 Guest

    That is why you don't load full power loads and you load towards the bottom end and fire form them. Like I said I never had a problem.

    Then again I don't use Hornady brass I found it too soft and didn't last as long as Remington. I have now switch all my 308 loads to Laupa brass.
  13. soundguy

    soundguy Well-Known Member

    May 8, 2012
    JLA are those LEE dies. looks like i saw a dipper.. and a clear plastic top under the yellow tray?

    I have some lyman dies in yellow boxes like rcbs.. but all my LEE dies are red clear plastic.. or red plastic trays with clear covers.

  14. JLA

    JLA Well-Known Member

    Feb 26, 2007
    Heart Of Texas
    yessir. My LEE .243 set is the only yellow box set i have.
  15. soundguy

    soundguy Well-Known Member

    May 8, 2012
    wow.. have never seen yellow boxed lee's :)
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