Barrel Burning and computing BC

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by ricka0, Jul 19, 2005.

  1. ricka0

    ricka0 Well-Known Member

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    I'm going to kill 2 birds with one shot. I was stressing over target practicing with my new Allen/Lilja RUMS - don't want to burn the barrels out. I thought I'd get a .308 for target practice - but then I need to get another good scope (or swap like mad).

    Why not just do reduced loads in my RUMS? Can't I get minimal barrel wear by using a cooler/slower load? I plan on getting the RSI pressure trace system so my loads don't get dangerous (too slow so they have pressure spikes).

    I was also stressing on how I could shoot thru my two chrono's at 1000 yards to determine the BC at that range (and velocity) - but now I've killed the 2nd bird. I can put the chrono close where I won't be so likely to take them out - AND do so at a lower velocity.

    sometime back there was a debate about fire forming brass in the garage with breakfast cereal. The primary advantage being longer barrel life? Can't you just use reduced loads to fire form without putting excessive wear on your barrel?
    I like the idea of target shooting with the same gun/scope I'll be hunting with - a milder load can be compensated for.

    comments? Suggestions?
     
  2. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    b1g_b0re,

    This is a good idea in theory but in reality, with cases with the capacity of the RUM cartridges, reduced loads really do not perform all that well as far as velocity consistancy and on top of that, powder fouling can become a huge problem with reduced loads at this case capacity.

    Now taking 150 fps off would probably be fine but dropping much less then that will result in poor performance all around from what I have seen

    I have never been a fan of fireforming with cornmeal. Extremely dirty and I have yet to see a properly formed case with sharp shoulders using this practice.

    Good Shooting!!

    Kirby Allen(50)
     

  3. 257speed

    257speed Well-Known Member

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    Kirby is right, cornmeal just does not generate enough pressure to give you the nice sharp shoulders. And who wants to sit in the garge making a big cornmeal dustcloud, when you could be outdoors killing paper. /ubbthreads/images/graemlins/grin.gif
     
  4. ricka0

    ricka0 Well-Known Member

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    Thanks for the responses.

    abinok also educated me offline. A load so low as to repro 1,000 yard velocity at only 20 yards would not stabilize a long heavy bullet - so you would get bogus results.