close
Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Rifles, Bullets, Barrels & Ballistics

Rifles, Bullets, Barrels & Ballistics Applied Ballistics

Reply

Velocity Magnatude Questions

LinkBack Thread Tools Display Modes
  #8  
Unread 04-21-2010, 09:04 PM
Platinum Member
 
Join Date: Jun 2001
Location: Potomac River
Posts: 5,071
Re: Velocity Magnatude Questions

The slower bullet will, as time goes by, get closer in speed to the faster bullet but it approaches it asymptotically and never ever becomes equal in speed with the faster bullet.

All you have to do is to run the same bullet such as the 300 SMK at 3200 fps and at 3300 fps and see what the speeds are at 1000, 2000, and 3000 yards.
__________________
The Smokin Fur Rifle Club
Reply With Quote
  •   #9  
    Unread 04-21-2010, 09:04 PM
    Platinum Member
     
    Join Date: May 2008
    Location: South of Canada and North of Wyoming
    Posts: 6,068
    Re: Velocity Magnatude Questions

    Quote:
    Quote:
    Originally Posted by eddybo View Post
    Yall seem to believe similar to my own thoughts on the subject. This started over on the hide. I had a post regard the 375/416 that I am going to be playing with. I was told that I would be launching the bullets too fast and that they would slow down to fast. I thought they were just jacking with me, but did not want call them on it. I finally got curious and sent a PM to one of the guys. He tried to explain it but I am not seeing it. Now I know one of these guys "Later" while we have never met have several mutual friends and have conversed on the phone several times.......is he jacking with me? Later knows a lot of crap I am sure he knows more minutia about external ballistics than I do. The only thing I know about this stuff is functional.

    416 barret brass quality??+ other ????s - Sniper's Hide Forums
    After reading that thread, "Later" is either jacking you around or doesn't have a clue what he is talking about. There are only two things that matte in external ballistics in short, medium, long or any range, and they are velocity and BC, period. It's very easy to demonstrate by playing with a ballistic calc. If you have two identical bullets leave the muzzle at different velocities, the faster one is going to get to the same point (any point) faster and go farther, and buck wind better. If you have two bullets leaving the muzzle at the same velocity, the one with the higher BC will get down range faster, blah, blah , blah, period. don't matter what caliber weight or anything else. BC and velocity are the only things that count. Just run a couple of ballistic calcs and ask "Later", uhhhh.... what abou this???
    Reply With Quote

      #10  
    Unread 04-21-2010, 09:14 PM
    Platinum Member
     
    Join Date: Jan 2007
    Location: MS
    Posts: 1,652
    Re: Velocity Magnatude Questions

    I dunno, yalls thoughts are the same as mine. I was just wondering if there was something I was missing, some obscure theory or something. I have run a 375 gr bullet with a BC of .94 though exbal using both velocities, faster always wins.
    __________________
    I admit that I know just enough to be dangerous.....but dangerous at ever extending distances.
    Reply With Quote
      #11  
    Unread 04-22-2010, 10:41 AM
    Platinum Member
     
    Join Date: Feb 2009
    Location: Sedalia, MO
    Posts: 1,256
    Re: Velocity Magnatude Questions

    Eddybo,

    after taking a peek at the link you posted to Later's comments, it seems to me that things were just taken a bit out of context. I didn't get that he was saying anything about identical bullets, or that the slower bullet would go further because of air drag, etc.. He's correct about the faster bullet suffering more resistance. This resistance is roughly proportionate to the square of the velocity, sort of like how kinetic energy is calculated. Double the velocity and you've roughly quadrupled the atmospheric resistance. However, once you compare two identical bullets that have arrived at the same velocity, the trajectory, energy, drag, etc., is going to be identical.

    Here's a simple illustration; Maximum range is acheived at a departure angle of 45 degrees in a vacuum. No atmospheric resistance involved in that case, so the departure angle is the same for the max range of any projectile. In the real world, that departure angle needs to be about 30-33 degrees for a typical centerfire rifle, due to the atmospheric resistance, i.e., drag. However, a typical mortar usually hits its maximum range when the departure angle is close to 45 degrees, just like the theoretical vacuum trajectory. The difference here is velocity. The mortars are typically fairly low velocity, and as a result suffer much less drag compared to a higher velocity projo. Any clearer now?

    Hope this helps,

    Kevin Thomas
    Lapua USA

    Last edited by Kevin Thomas; 04-22-2010 at 10:46 AM.
    Reply With Quote
      #12  
    Unread 04-22-2010, 03:32 PM
    Platinum Member
     
    Join Date: Jan 2007
    Location: MS
    Posts: 1,652
    Re: Velocity Magnatude Questions

    Kevin your explanation makes perfect sense, but the context is correct, based on PMs with one of the other posters.

    The premise still is that identical bullets launched at differing speeds, that the faster bullet will somehow travel a lesser distance. I cannot see it, but thought maybe my lack of a science background caused my blindness.
    __________________
    I admit that I know just enough to be dangerous.....but dangerous at ever extending distances.
    Reply With Quote
      #13  
    Unread 04-22-2010, 05:13 PM
    Platinum Member
     
    Join Date: Dec 2008
    Location: rathdrum, id.
    Posts: 5,015
    Re: Velocity Magnatude Questions

    Quote:
    Originally Posted by eddybo View Post
    Kevin your explanation makes perfect sense, but the context is correct, based on PMs with one of the other posters.

    The premise still is that identical bullets launched at differing speeds, that the faster bullet will somehow travel a lesser distance. I cannot see it, but thought maybe my lack of a science background caused my blindness.
    You see VERY clearly
    Reply With Quote
      #14  
    Unread 04-22-2010, 06:27 PM
    Platinum Member
     
    Join Date: May 2008
    Location: South of Canada and North of Wyoming
    Posts: 6,068
    Re: Velocity Magnatude Questions

    Quote:
    Quote:
    Originally Posted by elkaholic View Post
    You see VERY clearly
    Yes you do see cleary. I went back and read the thread again a little more slowly. Those guys really don't understand physics and ballistices very well at all. They dont even mention the term BC and misunderstand the relationships and meanings of velocity, energy, mass, inertia, etc. With many, if not most bullets, BC actually increases (increased resistance to drag) with velocity. For example these GS bullets...

    The GS HV .308 177, .638 @ 3300 fps, .603 @ 2450 fps and .589 @ 1600 fps.

    GS CUSTOM BULLETS - Specifications for use

    The GS SP .338 295, 1.010 @ 2850 fps, .973 @ 2025 fps and .760 @ 1200 fps.

    GS CUSTOM BULLETS - Specifications for use

    You will also see this with the SMK's. The ballistic calculators don't lie. The greater the velocity of a bullet, the faster it will get to point A and point B and point C and so on... and it will go farther, and it will buck wind better, etc., etc.
    Reply With Quote
    Reply

    Bookmarks

    Thread Tools
    Display Modes


    Similar Threads for: Velocity Magnatude Questions
    Thread Thread Starter Forum Replies Last Post
    Howa 1500 Questions in .223 Questions jaredagreen Rifles, Bullets, Barrels & Ballistics 15 04-02-2011 02:35 AM
    30-378 velocity SUNDEVIL Rifles, Bullets, Barrels & Ballistics 2 03-05-2008 07:57 PM
    XCR 338 RUM + HS Precision stock. Questions, Questions, Questions raisincenter The Basics, Starting Out 2 11-28-2007 02:44 PM
    BC and velocity of 195 ULD in 270 AM and 200 ULD in 7mm AM? sambo3006 Rifles, Bullets, Barrels & Ballistics 3 11-29-2006 06:47 PM
    300 wsm velocity 300win Reloading 0 11-21-2006 03:16 PM


    All times are GMT -5. The time now is 03:49 PM.


    Powered by vBulletin ©2000 - 2017, Jelsoft Enterprises Ltd.
    Content Management Powered by vBadvanced CMPS
    All content ©2010-2015 Long Range Hunting, LLC