Case length after sizing?

Discussion in 'Reloading' started by 243yote, Mar 4, 2010.

  1. 243yote

    243yote Well-Known Member

    Messages:
    77
    Joined:
    Apr 2, 2009
    I have read alot of articles on the forum and was wondering with all the talk about headspace and checking do you guys trim brass to min length with your shoulders -.002 back or how do you guys go about that? Also talking about neck tension after sizing would longer brass hold more that one that is trimmed shorter? :rolleyes:
     
  2. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,262
    Joined:
    Aug 10, 2003
    I trim brass only to get it to the same length -after it's fireformed (pretty much 3-4 reloads before any bumping will be needed).
    I never need to trim them again with my cartridges, loads, and given that I never FL size.

    If you do FL size, it's beyond me how this will affect case length from one to another. I imagine it depends on the cartridge.
    Neck tension from bushing dies could be affected by variance in neck lengths. But this affect is dependant on the overall sizing done. For me this would be a very small variance as I run with low tension.
     

  3. Fitch

    Fitch Well-Known Member

    Messages:
    478
    Joined:
    Aug 5, 2009
    I FL size new brass which doesn't do much besides make the neck round. Then I deflash the primer holes and trim it to length. My ammo is for practical purposes all hunting ammo so I adjust the die to bump the shoulders ~.002" and FL size after each firing. Then I check for case length and trim if required but "always" after sizing.

    Fitch
     
  4. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,262
    Joined:
    Aug 10, 2003
    Really?
    You measure every case after FL sizing everytime?
    What cartridges?
    How much has FL sizing been affecting length on em?
     
  5. Fitch

    Fitch Well-Known Member

    Messages:
    478
    Joined:
    Aug 5, 2009
    Yup.

    .17 Remington, .22-Hornet, .223, .22-250, .243, and .30-06.

    The Wilson trimmer is pretty fast, really precise, and once set doubles as a case length gage.

    The .30-06 is the only case that "needs" trimming after every firing. It seems to grow like corn on a hot humid summer night even though the sizing die only bumps the shoulders about .002". The chamber in that rifle is quite rough - the stretch happens just above the base thinning the cases into unusability in 7 firings. I'm going to polish it a bit as one of this winter's many projects. It comes to the to of the list right after I bed two more rifles.

    Like most things, this came about because of a learning experience. I had some .223 brass that grew too long - long enough to cause a sticking bolt (but no other pressure signs). In looking for the cause I measured the chamber and the brass and was able to prove the brass had grown too long for the chamber. Nothing bad happened, but I didn't want to have any future issues, so I started checking the brass after sizing by dropping it in the Wilson Trimmer. With all but the .30-06, and to some extent the .17 Remington, it bare touches the case mouth, but it always leaves the case mouths square and I have a clean bevel for seating bullets.

    Works for me. YMMV.

    Fitch
     
  6. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,262
    Joined:
    Aug 10, 2003
    Thats alot of work.. FL sizing, trimming, rechamfering, every case, every time.
    Sounds like you got it down Fitch. But no,, I would not do it. And thankfully, I don't have to.

    This is where a better sytem of cartridge design, chamber dimension control, and minimal sizing really pays off I guess.
    I shoot 223, 6br, 6xc, and 6.5wssm now.
    Neck dies are Wilson[partial NS]
    Body dies are Redding/JLC Precision[shoulder & web bump]
    Never FL sized a case in my life, and I'm feeling better about that everyday.