Results 1 to 9 of 9
  1. #1

    Default 308 Ballistic Coefficient

    HI
    Does any body know the ballistic coefficient of the FMJ 143grain 308 point .

  2. #2
    Banned
    Join Date
    Aug 2012
    Location
    Stella
    Age
    46
    Posts
    10,870

    Default Re: 308 Ballistic Coefficient

    Chuckhawks:

    The Sierra 150 grain boat tail spitzer has a ballistic coefficient (BC) of .416 and a sectional density (SD) of .226.

    Hope it helps!

  3. #3
    User
    Join Date
    Dec 2010
    Location
    Philippolis
    Posts
    4,733

    Default Re: 308 Ballistic Coefficient

    According to PMP the BC is .456, this is from the March 1998 Magnum.

  4. #4
    Banned
    Join Date
    Dec 2009
    Location
    Vereeniging
    Age
    70
    Posts
    5,782

    Default Re: 308 Ballistic Coefficient

    I see that Quick Load also lists the G1 as 0,456 for this bullet.

  5. #5
    User
    Join Date
    Oct 2012
    Location
    Noord van die biltong gordyn.
    Age
    56
    Posts
    9,116

    Default Re: 308 Ballistic Coefficient

    Quote Originally Posted by TStone View Post
    According to PMP the BC is .456, this is from the March 1998 Magnum.
    Depending on what type of program you are using, you have to make some adjustments to the quoted BC figure, to get more accurate predictions. If your program uses a single "G1" BC figure, use 0.40. (G1 is not really all that relevant to Spitzer-BT bullets, and the BC figure decreases as bullet velocity goes down.)

  6. #6
    User
    Join Date
    Jul 2009
    Age
    52
    Posts
    77

    Default Re: 308 Ballistic Coefficient

    no ways will it have a .456 bc that's better than a lot of 155gr match bullets.Got some will test them
    myself to check bc values.

  7. #7

    Default Re: 308 Ballistic Coefficient

    Quote Originally Posted by archer View Post
    no ways will it have a .456 bc that's better than a lot of 155gr match bullets.Got some will test them
    myself to check bc values.
    How do you actually test the BC of a bullet?

  8. #8
    User
    Join Date
    Oct 2012
    Location
    Noord van die biltong gordyn.
    Age
    56
    Posts
    9,116

    Default Re: 308 Ballistic Coefficient

    Quote Originally Posted by boesman10 View Post
    How do you actually test the BC of a bullet?
    No short answer there. A good read, to explain all the intricacies, in easy understandable language is: "Applied ballistics for long-range shooters" by Bryan Litz.

    In short: The commonly quoted G1-referenced BC figure, is not constant for most Spitzer-BT bullets. It starts high, and decreases as velocity deminishes. So .456 might be possible at about 4000 fps, but not at 2500 fps, assuming std atmospheric conditions, at sea level.

    With most trajectory predictions, you still have to test physically. Adjust the figures you feed your computer, untill the trajectory predictions match with your actual range results. That's the fun part...

  9. #9

    Default Re: 308 Ballistic Coefficient

    Quote Originally Posted by A-R View Post
    No short answer there. A good read, to explain all the intricacies, in easy understandable language is: "Applied ballistics for long-range shooters" by Bryan Litz.

    In short: The commonly quoted G1-referenced BC figure, is not constant for most Spitzer-BT bullets. It starts high, and decreases as velocity deminishes. So .456 might be possible at about 4000 fps, but not at 2500 fps, assuming std atmospheric conditions, at sea level.

    With most trajectory predictions, you still have to test physically. Adjust the figures you feed your computer, untill the trajectory predictions match with your actual range results. That's the fun part...
    sorry for resurrecting this old post, but did you manage to test the bc on this 143gr PMP FMJBT?

Similar Threads

  1. Ballistic Nutcracker
    By Bearded One in forum Getting Started on Gunsite
    Replies: 6
    Last Post: 14-12-2014, 08:07
  2. 9mm Ballistic Chart
    By Castos in forum Ammunition
    Replies: 0
    Last Post: 13-09-2014, 11:17
  3. Ballistic Test
    By Gerkie in forum General Discussion
    Replies: 5
    Last Post: 21-11-2012, 13:10
  4. Ballistic coefficient
    By Anwar in forum Ammunition
    Replies: 10
    Last Post: 17-12-2008, 15:44

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •