Chambering ???

Discussion in 'Gunsmithing' started by shortpants, Jan 18, 2012.

  1. shortpants

    shortpants Well-Known Member

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    Let's say I'm having a custom built with the intentions of shooting 210vld's but down the road might want to experiment with the 230vld's. Would I have to chamber for the heavier bullet or would it matter?
     
  2. Gunpoor

    Gunpoor Well-Known Member

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    I don't know what cartridge you plan on building, but I am thinking probably a .308" of some ilk. I don't think chamber dimensions would matter between two bullets so close in length. Make sure the bore twist rate is fast enough to stablize the heaviest bullet you plan to shoot. I make it a rule to err on the side of too fast of twist rather than too slow.
     

  3. bigngreen

    bigngreen Well-Known Member

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    You can always cut more metal out but you can't put it back :D
     
  4. Hired Gun

    Hired Gun Well-Known Member

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    I believe the ogive on both those bullets are pretty close. You don't want them touching the rifling anyway and if this is a repeater you may not reach them anyway. They say the 1-10 twist should stabilize the 230 just fine. I haven't tried them myself yet but plan to try to this summer some time.
     
  5. shortpants

    shortpants Well-Known Member

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    Thanks for the responses guys. It sounds like in the case of theses 2 bullets it's a non issue. For the sake of me understanding the theory behind my question let's imagine a 230gr. and a 162gr. Amax. How would you chamber the bbl? I think I know the answer and apologize for asking a dumb question but am just curious how limited you are when you build a rifle around a particular bullet?
     
  6. Topgun 30-06

    Topgun 30-06 Well-Known Member

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    I'm not quite following you on your question "chambering the bbl". The case that holds the bullet in the chamber is what you are building around. If you want various bullet weights and lengths, then you need to look and see if the case you want to build around will shoot those particular weight bullets. Then you need to look and see what twist in the barrel is suggested for those particular bullets to impart the correct spin rate for the best accuracy.
     
  7. Gunpoor

    Gunpoor Well-Known Member

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    I think what shortpants is asking is if the free-bore needs to be fitted to a particular length of bullet. I think you could ask a dozen custom rifle builders and shooters and get at least a half dozen different answers. Myself, I like to be able to reach the lands with the bullet I am shooting, BUT that doesn't necessarily mean that I will seat the bullets to that length. I have found that seating bullets with a somewhat long jump to the lands doesn't detract from accuracy if the load has been developed around that much jump. There are just no concrete answers to questions about this.

    Having said all of the above. I it were me shooting two extremely different length of bullets in one rifle I would set the free-bore so that the longest bullets would be seated fairly deep and work up a load with this COAL, and the shortest bullets seated as far out as would be safe and practical and develope the load for the amount of jump (if any) that is incurred with that COAL.
     
  8. Topgun 30-06

    Topgun 30-06 Well-Known Member

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    That makes more sense and I think your reasoning for doing as you stated with the two different bullet lengths is sound advice. Thanks!!!
     
  9. shortpants

    shortpants Well-Known Member

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    Thankyou Dennis that is exactly what I meant. That is also the answer that I figured would be the way to do it. Dreaming up my first build and asking questions as they enter the space between my ears. Sometimes they are silly questions but I'm learning.