Rifling Angle to Bullet?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Bart B, Dec 18, 2009.

  1. Bart B

    Bart B Well-Known Member

    Messages:
    2,483
    Joined:
    Dec 25, 2005
    Here's three barrels:

    22 caliber (.224" groove diameter), 1:8" twist.

    30 caliber (.308" groove diameter), 1:11" twist.

    44 caliber (..448" groove diameter), 1:16" twist.

    Which one has the greatest angle the rifling presents to the bullet?
     

  2. J E Custom

    J E Custom Well-Known Member

    Messages:
    7,257
    Joined:
    Jul 29, 2004

    The 1 in 8 twist.

    The faster the twist the greater the angle.

    Twist rates are based on the inches it takes for the bullet to make one full revolution=
    1in 8 = 1 reveloution in 8" and so fourth.

    J E CUSTOM
     

  3. NomadPilot

    NomadPilot Well-Known Member

    Messages:
    510
    Joined:
    Aug 28, 2009
    All the same angle.
     
  4. Mikecr

    Mikecr Well-Known Member

    Messages:
    4,246
    Joined:
    Aug 10, 2003
    The factors here amount to circumference traveled per bore travel
    [2 sides of a triangle]

    InvTan(Pi*Diameter/Travel)
    All three are ~5 degrees
    (I think)
     
    Last edited: Dec 19, 2009