Yikes. What do I do now?

Discussion in 'Reloading' started by Troutslayer2, Aug 30, 2010.

  1. Troutslayer2

    Troutslayer2 Well-Known Member

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    I went out to ladder test today. I was using some RP brass, which I bought as .280 rem, and fired in the rifle to change them to .280AI. They didn't shoot very well. Anyway, I used a neck sizer die only on them, and then reloaded a ladder that was going to go all the way up to 61.5 grains. I started getting case separation signs at about 57.5, and this happened at 58 grains. [​IMG]

    Could someone give me the quickload data for this load?
    4000 Feet elevation, 70 degrees
    .280 Ackley Improved
    160 Grain Nosler Accubond
    58 Grains Reloader 22
    26" Bbl, 1:10 Twist

    The only thing that I can think of is that when I fired the Remington factory stuff, nearly all of the primers were lifted out of the primer pockets. I took this as a sign of low pressure, was I wrong? I do not know what to make of this, probably because I am inexperienced. I am a good ways back from the lands. From everything I've read, I should not be getting this much pressure with this load, so I either have a crappy batch of brass or a hot jar of powder- or I have other problems. Any advice?

    Ladder test was an epic failure, but the dispersion on the lower end of things was very good and I hope that I am getting enough velocity at around 56.5 grains. I need a chronograph bad.
     
  2. str8shoot

    str8shoot Well-Known Member

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    Wow! 2.5 grains under Nosler's max load for .280 ai, and... that looks scary!
    Did you trim your brass after neck sizing? When you fire-form brass from a .280 you have extra headspace this probably stretched the web area. If you didn't trim your brass, your case may have been too long, spiking pressure. A spike like that will find the weekest part of your case.
    The shoulder of a .280 case is farther back than a .280 ai causing exta headspace while fire forming. However, the case length of the .280 is longer than that of the ai. Therefore trimming will be necessary.
    Hopefully others with more experience than me will chime in. I wouldn't shoot that rifle again until i was sure I figured this one out!
     

  3. Troutslayer2

    Troutslayer2 Well-Known Member

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    The twice fired RP brass measures 2.529", which is shorter than the .280AI Nosler brass that is new, that is the only thing I based my OAL on because I don't have a drawing of the .280AI case. It chambers and is shorter than the factory stuff. I have cleaned the gun several times, but carbon ring built up maybe? I didn't have this issue with Berger bullets, only the accubond.
     
  4. bigngreen

    bigngreen Well-Known Member

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    Did you fire form with the bullet into the lands to keep the case firmly against the bolt face? If not what happens is you end up moving the brass at the case head instead of along the length of the case making a thin spot at the case head.
     
  5. str8shoot

    str8shoot Well-Known Member

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    My nosler manual has 2.525 as the maximum case length for the 280 ai. They list 60.5 as the max for RL22.
    I'm with bigngreen on the the case stretching at the web.
     
  6. hypersonic

    hypersonic Well-Known Member

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    How hard was it to open the bolt on the rifle and was the case hard to extract? Your chamber might be a little on the large side and that could be the cause of the primer problems you saw with the factory ammo. If it was me in your situation I would try to get some nosler 280ai brass and start working up again watching my primers closely. If you can't get the nosler brass and you have to fire form Rem brass pick up some cheaper cup and core bullets that are long enough to allow you to put the bullet into the lands and use a starting load for the 280 Rem with one of the medium burn rate powders you should be able to find data for the 4895's 4064 and perhaps some others. When loaded you should have some resistance to chamber the loaded round. I would measure any fired cases and compare my measurements to the measurements of the 280AI. If there is a large difference in your fired brass versus the accepted measurements for the AI with the 40 degree shoulder I would have a chamber cast done just to see exactly what is going on the the chamber dimentions.
     
  7. Troutslayer2

    Troutslayer2 Well-Known Member

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    Crap! I didn't know I was supposed to do that. I have 40 pieces of Nosler brass which I bought loaded .280Ai. They don't have any brass right now due to fire. To get the RP brass I just bought boxes of Corelokt and have been shooting them up to get brass to work with- so all that brass is now worthless? Upon closer inspection, every single piece, even the super-low charges have some sign of not being right, from a faint mark to a raised line, to the worst one in the picture.

    None of them were difficult to extract. Thanks for the help. Next time- into the lands I guess. I was thinking it was caused by a very tight chamber, but I was wondering just how the primers could have lifted if that were the case.
     
  8. bigngreen

    bigngreen Well-Known Member

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    Neither did I :D

    What happens is when you fire the case is moved forward by the firing pin to the shoulder as the main charge fires the case forms to the sidewalls and grabs them, then the primer comes out a bit and finally the case head slams into the bolt face flattening the primer like a pancake and thinning the brass right at the case web then you size it and finish it of.
    You want the bullet to hold the case back and have it blow forward forming the AI shoulder from back to front.
     
  9. Troutslayer2

    Troutslayer2 Well-Known Member

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    thanks bigngreen, where in SW MT are you? I am in Missoula. Have lived in Alberton and also in N. Idaho. If you ever need an understudy, intern or anything, I would love to get together and shoot with some people around here who know what they're doing.
     
  10. bigngreen

    bigngreen Well-Known Member

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    I'm in Dillon. Broz put on a couple shoots this year at the Townsend range, well worth the drive! He's done for this year but watch for it next year. Rounds fired and LRH are very good teachers, IMHO :D http://www.longrangehunting.com/forums/f36/montana-long-range-get-together-shoot-57460/
     
  11. tim jurczak

    tim jurczak Well-Known Member

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    Same thing was happening to me w/ 7RUM and RL25. Higher charges did it worse. Called all over trying to get answers and then noticed the foot note in Nosler load manual stating this problem would happen if necks did not seal completely. I anealled necks and problem solved. Hope you get it sorted out.


    Tim J.
     
  12. BountyHunter

    BountyHunter Writers Guild

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    setting up a false shoulder is a better way to do that and you can see articles and pics on how at 6mm.br.com

    BH
     
  13. Troutslayer2

    Troutslayer2 Well-Known Member

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    Thanks for all the help on this. I have got things figured out. Here is a riddle for you:

    So I have several boxes of .280 Remington 140 gr. Corelokt that I bought specifically to fireform in this rifle. Since we have learned that this isn't going to work without the bullet being jammed into the lands- can I just use my kinetic bullet puller, give em' a couple of whacks to get them long enough to be jammed and then fire them, or would the charge possibly be too high???? It would save me a lot of time to do it that way, but is it a bad idea?
     
  14. SBruce

    SBruce Well-Known Member

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    You can try it, but you really need quite a bit of neck tension on the bullet to seat them long and fireform. Might be better off pulling them, dumping powder, resize the necks again, charge and load long. As mentioned before, it should be somewhat hard to close the bolt on a loaded round.

    I am seriously wondering if you have an oversize chamber too. Reason I say this, is that the older AI cartridges were supposed to be able to form by just simply shooting factory ammo (where the bullets ARE NOT seated long). Of course, the 280 AI isn't really an older AI in my opinion........makes me wonder if the shoulder is actually moved forward quite a bit on a 280AI (longer case body AND sharper shoulder angle)???

    Let us know how this works out for you.
    Good Luck.
     
    Last edited: Sep 11, 2010