Throat Wear and Barrel Life

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • dega37
    Bloodstained
    • Nov 2014
    • 87

    Throat Wear and Barrel Life

    Horde,

    What are your thoughts on throat wear and barrel life? It seems that barrel life is more related to velocity than how much powder is in a cartridge. If one was shooting an Ultra-mag for example and changed the bullet and powder combination so that the bullet was only going 2600 fps, would it still be a barrel burner? Anyone have experience with this?
    Last edited by dega37; 01-21-2017, 10:37 PM.
  • Klem
    Chieftain
    • Aug 2013
    • 3509

    #2
    Unsure what you mean by 'more proportional'. All other things being equal I image they both have unique and measurable correlations.

    I would add the barrel diameter and metallurgy are other influential factors here.

    Comment

    • dega37
      Bloodstained
      • Nov 2014
      • 87

      #3
      yeah changed it to "related". Also assuming metallurgy is the same. Are you saying the thicker the barrel, the better barrel life?

      Comment

      • Texas
        Chieftain
        • Jun 2016
        • 1230

        #4
        Originally posted by dega37 View Post
        yeah changed it to "related". Also assuming metallurgy is the same. Are you saying the thicker the barrel, the better barrel life?
        Barrel life can be described in a number of ways, but generally has to do with throat erosion and wear on the last 4" or so of the barrel. Throat erosion can be effected by the powder used as much as anything else. If you load a cartridge with a given weight of bullet and a max charge of IMR4831 and do the same thing only change the powder to IMR4895, after a few shots you will see a dramatic difference in the heating of the barrel. IMR4831 will heat the chamber area, and the brass will come out too hot to hold while with IMR4895, the last 6 or so inches of the barrel will be very hot, and the brass will come out so that you can hold it in your hand no problem. I shot 420 rounds of 5.56X45 out of an M4 in less than 3 minutes, and the rapid fire caused significant gas checking in the throat and the gas port but had little noticeable effect on the last 6 inches of the barrel when looked at through a scope. The forestock got so hot it caught fire. The lesson learned was the effect that excessive heat caused the barrel to fail even with a chrome lining.

        Comment

        • LRRPF52
          Super Moderator
          • Sep 2014
          • 8569

          #5
          Steel hardness
          Over-bore
          Shoulder Angle
          Chamber pressure
          Bearing surface

          Light off an energetic plasma conversion at 58,000-65,000psi, then funnel it through a tight neck and throat-especially with lower angle shoulders (20 degree as an example), and you'll get early throat and consequential bore erosion.

          Use an efficient chamber/cartridge design with higher shoulder angle (30 degrees or more), less chamber pressure, less over-bore (case diameter to neck diameter) and you get long barrel life.
          NRA Basic, Pistol, Rifle, Shotgun, RSO

          CCW, CQM, DM, Long Range Rifle Instructor

          6.5 Grendel Reloading Handbooks & chamber brushes can be found here:

          www.AR15buildbox.com

          Comment

          Working...
          X