.243 improved help ?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by b1det, Dec 28, 2012.

  1. b1det

    b1det Member

    Messages:
    14
    Joined:
    Sep 3, 2011
    Last night I was reading about .243 ai and stumbled on a thread were it was being talked about pro's, con's and so on but a post discussion about .243 improved lr was mentioned and vary similar to the ai but slightly different. The other chamber was 1 less gr of water butt shorter col . I think this would favor a gas gun better, does this sound familiar to any of you?
     
  2. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,252
    Joined:
    Aug 10, 2003
    You talkin bout this? Super LR
    There are so many improved 243s that it's difficult to know.
     

  3. b1det

    b1det Member

    Messages:
    14
    Joined:
    Sep 3, 2011
    Yes that's it, I tried all day and rite after I posted found it. How does it stack up against the 243ai ?
     
  4. elkaholic

    elkaholic Well-Known Member

    Messages:
    5,290
    Joined:
    Dec 4, 2008
    My personal opinion on the .243 case is that any gains made from wildcatting it would be so minimal as to not be worth the hassle unless you just want something different. The .243 does not have a lot of body taper in its stock form and also has a fairly sharp shoulder and adequate neck.....Rich
     
  5. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,252
    Joined:
    Aug 10, 2003
    I don't have either. I've shot a 6XC for a while(another improved 243).
    Just looking over the 243AI -vs- 6SLR
    The 243AI has a 40deg shoulder and lower body taper than the 30deg 6SLR. It also holds a little more capacity. This would provide for better brass life, but at the further expense of barrel life(243 is already a barrel burner). 6SLR improves barrel life and brass life(a little)over a 243.

    There may have been exceptional loads found with the 6SLR & this might tip the scale.
    Another similar is the 6CM, which has made a lot of competitors happy.
    6CM testing Results
     
  6. b1det

    b1det Member

    Messages:
    14
    Joined:
    Sep 3, 2011
    How much of a gain is to be had in the throat erosion . I have read that even ackly thought the .243 was improved but made the chamber and was pleased with the decreases in brass stretch. Thanks to all for the insight.
     
  7. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,252
    Joined:
    Aug 10, 2003
    The gain in improving a cartridge with lower body taper and higher shoulder angles is:
    - Target capacity for bullets and powders available
    - Less brass stretch, so less sizing needed, so longer case life
    - Improved internal ballistic efficiency, because more powder is burned in/near the chamber, instead of merely adding to bullet mass(increasing recoil and muzzle pressure)

    If your talking throat erosion as a matter of flamepoint setup by shoulder angles, I don't know that this has been tested & proved beyond notion. But I don't know of anything 'bad' in higher shoulder angles -except for feeding. You might want to consider feeding, as not any ole action does this well with improved cartridges. At 40deg you may need single shot feeding, even with a coned breech.
     
  8. marshal

    marshal Well-Known Member

    Messages:
    81
    Joined:
    Dec 16, 2010
    I just built one, (.243AI) it's one of my most accurate rifles to date.. 8 twist Shilen, 117gr Matrix on top of 47.5gr H1000, Velocity?? but crazy accurate.
    I'm not sure you could get 47.5gr of H1000 into a .243 win case?
    I cannot see for the life of me why people seem to feel the need for 7 twists unless running at lethargic velocities. My 2bits.. good cartridge
     
  9. b1det

    b1det Member

    Messages:
    14
    Joined:
    Sep 3, 2011
    We'll I am looking at buying a dpms in .243 win and have a hell of a time leaving well enough alone been doing a lot of reading. I don't have enough experience, so input from all of you helps a ton and I learn all the way through. It's a win win for me it will be my first gas gun is there anything I should know ?I am buying used the gun shows well I really wanted a 6.5 but am unable to find one. DPMS says one year before comp uppers are available. Thought I could have some fun and learn a lot at the same time. Thanks-Brian
     
  10. b1det

    b1det Member

    Messages:
    14
    Joined:
    Sep 3, 2011
    Can you shoot and fire form .243 win in the 6mm super lr like you can in the .243 ai ?
     
  11. Nimrodmar10

    Nimrodmar10 Well-Known Member

    Messages:
    785
    Joined:
    Aug 21, 2011
    If you're wanting a gas gun in 6.5 why not step up to the AR10 and get it in a 260 Rem.

    I put one together a couple of years ago and it's a shooter with the 130 gr. Bergers and the 140 gr. Nosler Balistic Tips. I built it for a long range suppressed gun so it is on the heavy side.

    But if you're wanting to thin out the deer in the soybean fields, just put the suppressor on it and let her rip. At 300-500 yards they just mill around not knowing where the shots are coming from. Ugly but effective.
     
  12. timmyatnop

    timmyatnop Well-Known Member

    Messages:
    387
    Joined:
    Sep 22, 2009
    I had kevin cram build me a 6mm CM. Ive been loading 115 bergers vlds over 49grains h1000.. its crazy accurate.. ive been waiting on my ced m2 to show up. So ill have a better idea of velocity. Was gona do it last weekend but no chrono yet.