close
Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Reloading

Reloading Berger Bullets

Reply

How do I calculate MV? No Chrono.

LinkBack Thread Tools Display Modes
  #1  
Unread 08-26-2009, 08:17 PM
Silver Member
 
Join Date: May 2005
Location: Missoula, MT USA
Posts: 278
How do I calculate MV? No Chrono.

Is calculating MV more like a best guess without a chronograph or can I get pretty close knowing barrel length, powder, bullet weight? What kind of formula/freeware do I use?
Reply With Quote
  •   #2  
    Unread 08-26-2009, 08:29 PM
    Platinum Member
     
    Join Date: Oct 2005
    Location: Michigan
    Posts: 2,232
    Re: How do I calculate MV? No Chrono.

    Using the load info will not get you accurate enough for much, as different rifles behave much differently.

    If you have a drop chart and all the environmental conditions, you can work backward and get a fair guess with one of the ballistic programs.

    For example my 7mm Rem Mag, shooting 160gr Accubonds is sighted in at 200yds, the sight hieght is 1.5" and I have to crank 14.75 moa up to hit at 800yds when at 7480' elevation. By playing around with the program I can see that I am around 3000fps.

    My chrono tells me That I average 3015.

    Your best bet is to spend a couple hundred $$'s on a good chrono and use it. It will save it's cost in ammo over the next few years.

    HTH,

    AJ
    __________________
    If some is good and more is better, then too much is just right.


    My mind is a raging torrent, flooded with rivulets of thought, cascading into a waterfall of creative alternatives
    Reply With Quote

      #3  
    Unread 08-26-2009, 09:02 PM
    Silver Member
     
    Join Date: May 2008
    Location: Ohio
    Posts: 248
    Re: How do I calculate MV? No Chrono.

    This may seem like a smartass answer buuuuuut:

    If you have time lapse videography you could calculate the time it takes the bullet from the muzzle to some point downrange. I would expect this could cost a boat load, OR get a chrony for a lot cheaperů
    OR,
    Guess based on currently available data from ammunition mfrs - would be as good as not having a chrony.

    Regards,
    Lever
    Reply With Quote
      #4  
    Unread 08-26-2009, 10:43 PM
    Platinum Member
     
    Join Date: Jul 2004
    Location: Texas
    Posts: 6,923
    Re: How do I calculate MV? No Chrono.

    Quote:
    Originally Posted by AJ Peacock View Post
    Using the load info will not get you accurate enough for much, as different rifles behave much differently.

    If you have a drop chart and all the environmental conditions, you can work backward and get a fair guess with one of the ballistic programs.

    For example my 7mm Rem Mag, shooting 160gr Accubonds is sighted in at 200yds, the sight height is 1.5" and I have to crank 14.75 moa up to hit at 800yds when at 7480' elevation. By playing around with the program I can see that I am around 3000fps.

    My chrono tells me That I average 3015.

    Your best bet is to spend a couple hundred $$'s on a good chrono and use it. It will save it's cost in ammo over the next few years.

    HTH,

    AJ

    +1

    Before I could afford a chronograph I did about the same thing. I would shoot 5 rounds (Minimum) at each distance. 100,200,300,400,500,600,and on some rifles 1000 yards
    using a target large enough to get all of the groups on it.(I used the brown rapping paper
    on a 4" roll 4 to 6 ft tall.

    Then I placed a contrasting aiming point placed at 12 o'clock high and aimed at it for each
    group of shots at each distance.

    When I was through I found the center point of each group at that distance and used the
    drop to make my chart.

    Then using the reloading manual from the bullet manufacturer I matched the drop to the
    ballistic tables for that bullet weight and it got me close to the average velocity.

    And after many years I finally broke down and bought a chronograph and boy was it easier.

    And for working up loads much faster.

    J E CUSTOM
    __________________
    "PRESS ON"
    Reply With Quote
      #5  
    Unread 08-27-2009, 09:57 AM
    Platinum Member
     
    Join Date: Oct 2007
    Location: Mountians of SW NC, near Asheville
    Posts: 1,595
    Re: How do I calculate MV? No Chrono.

    "How do I calculate MV? No Chrono. "

    You can't. That's why we buy chronographs if we really want to know.

    I've seen book data off as much a 300 fps, both ways, for "max" book loads. I've also seen a midrange book load blow primers in a new rifle, meaning our books are only a guide and not a real good one at that; they simply can't be.

    Last edited by boomtube; 08-27-2009 at 10:01 AM.
    Reply With Quote
    Reply

    Bookmarks

    Thread Tools
    Display Modes


    Similar Threads for: How do I calculate MV? No Chrono.
    Thread Thread Starter Forum Replies Last Post
    How to calculate windage? cornchuck Long Range Scopes and Other Optics 6 03-13-2010 11:16 PM
    how do i calculate m.o.a and clicks for this? nathank Rifles, Bullets, Barrels & Ballistics 11 11-12-2008 08:39 AM
    Anyone ever chrono 300 WSM? goodgrouper Rifles, Bullets, Barrels & Ballistics 13 01-22-2008 10:39 PM
    chrono ?'s and more splattermatic Reloading 3 12-20-2006 02:03 PM
    How do I calculate the ballistic coefficient? Troutslayer Rifles, Bullets, Barrels & Ballistics 6 05-17-2005 08:52 PM


    All times are GMT -5. The time now is 04:54 AM.


    Powered by vBulletin ©2000 - 2016, Jelsoft Enterprises Ltd.
    Content Management Powered by vBadvanced CMPS
    All content ©2010-2015 Long Range Hunting, LLC