375 RCBS seating problem

Discussion in '.375 & Up' started by JamieD, May 22, 2011.

  1. JamieD

    JamieD AH Veteran

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    I have been having a problem with my RCBS seating dies in both my 375 RUM and H&H. When loading barnes tsx with compressed powder charges the bullet and seating die seem to form a vacuum. When I pull the cartridge out of the die it pulls the bullet part way back out of the case. This happens with very little compaction like only one or to percent.

    Does anyone have any ideas? Any help would be great.
     
  2. PHOENIX PHIL

    PHOENIX PHIL AH Legend

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    I have one idea, but please don't take it personally. This is exactly what happened to me loading for my now long gone .300 RUM. It was completely the fault of yours truly assuming Nosler powder loads would be okay for the TSX bullet. So I hate to ask this, but are you using the Barnes manual? I was being cheap and didn't buy it, I have since.

    Be very careful here!! My mistake led to a "high pressure event" that required fortunately only the gun being repaired and not the idiot reloader/shooter too.

    BTW, I don't think it's so much a vacuum as much as there's pressure being built up in the case and when you bring the press back down there's enough pressure to push the bullet out a bit. I was trying to blame the bullets as having non-uniform engagement with the forcing cone of the die. When I finally decided to check the Barnes manual I found I was way way way overcharging.
     
  3. WST416

    WST416 AH Veteran

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    First I don't know witch powder or what grain tsx your using, but if the loads are compressed you are right at the max charge probably. If you are new to loading these bullets I would suggest starting at the min and working up. This will also give you incite if when you reduce the powder charge the bullet stays seated. I have never heard of a vacuum inside the die that would pull the bullet back out, and seems even more strange that this is happening with to different calibers and dies. If you are loading based on another Barnes bullet or another manufacturers bullet beware as the same weight bullets are not necessarily the same length and when loading to the oal you may be seating that bullet deeper into the case. So what may be 102% with one bullet maybe 107% with the other bullet with the same powder charge when seated at the same oal. Barnes does have reloading data on line to double check you loads. Don't know if this the problem or not but a good place to start. good luck
     
  4. JamieD

    JamieD AH Veteran

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    Thanks for the incite. However I am still under the max load in the Barns manual with both guns my thinking was that rcbs uses the same seater for the H&H and RUM. The strange thing, and what makes me think it is creating a vacuum, is that once it does this it will nearly pull the bullet all the way out of the case. The only way I can get it to stop, is put a cleaning patch on the front of the bullet when I put it in the die. VERY BAD FOR UNIFORMITY.

    When you look at the data for the RUM in the barns manual many of the loads are at 100-107% so this really limits my powder choices. Thanks for the discussion.
     
  5. James.Grage

    James.Grage GOLD SUPPORTER AH Legend

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    JamieD

    Now i know that this is along shot have you called both the die maker with this problem?

    And how about the bullet manufacture on this problem with there bullet?

    Many times they will have an answer for you...

     
  6. PHOENIX PHIL

    PHOENIX PHIL AH Legend

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    How are you sizing the brass? You said it nearly pulls the bullet completely. This makes me wonder about the neck tension.
     
  7. PHOENIX PHIL

    PHOENIX PHIL AH Legend

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    Jamie, I wanted to expand on this post. I didn't have time this morning to fully explain.

    In an attempt to develop an accurate load for my .300 WM using TSX/TTSX bullets, I tried a number of things. One of these was to use a Lee Collet neck sizer. This neck sizer uses a collet to squeeze the neck down to the size of mandrel that is fed into the neck. The default size mandrel is sized to have a looser neck tension than my RCBS full length resizer. The difference was about 2.5 to 3 mils. This is intentional on Lee's part. This really wasn't a problem using bullets other than the TSX/TTSX, but it was with the Barnes bullets. My understanding is the TSX/TTSX are slightly smaller in diameter than lead core bullets to ensure there is less pressure.

    As a result, when I used the Lee neck sizer, I found exactly what you did. The bullets would either be very long or not seated at all.
     
  8. JamieD

    JamieD AH Veteran

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    Thanks for the input I thought there might be a quick fix to my problem. No such luck. I called RCBS they told me to send them 3 bullets and 16.95 + 4.95 S&H and they would make me a custom seater. This got under my skin a bit when I paid $30 for the die set then need to pay another 20 to use them. At least they were quite helpful.

    Hoping to save the dough I called Barnes they seemed like this is not an odd issue and told me to steel wool the inside of the seater. Saying there is sometimes a sharp edge. Tried this and it didn't work. He was very helpful as Barnes usually is. So not wanting to waist any more time (working up loads for August, can't wait,) I bit the bullet so to speak and mailed the bullets and $ to RCBS. They say they should have them made in 2-4 weeks.

    Until then I'll work with the 416.

    Hope no one else has this problem, but if they do maybe this post will help them along.
     
  9. PHOENIX PHIL

    PHOENIX PHIL AH Legend

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    Wow, that really seems wrong. I've not had to deal with RCBS customer service but have always heard good things. One thing I have noticed about my RCBS seater is that they frequently leave a mark on my bullet, I'm guessing it's a sharp edge on the seater. Perhaps yours is even sharper and enough to "grab" the bullet. A little polishing might help, but if you've sent it off already..

    Good luck with it, it sucks to have something like this pop up when you're getting ready for a trip.
     
  10. Mark H. Young

    Mark H. Young AH Senior Member

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    Jamie,

    Good luck with the custom seater. Loading monometal bullets is a little different. One thing that may help with load compression is to use a drop tube and and fill the case slowly. It will make a remarkable difference in the space left in the case once the powder is poued in.
     

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