Difference in velocity

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by little black 243, Apr 21, 2008.

  1. little black 243

    little black 243 Well-Known Member

    Messages:
    74
    Joined:
    Feb 25, 2008
    I am thinking about rebarreling my rem 700 7mm rem mag and was wondering what the velocity difference would be between a 24" and a 26" barrel? I need a good packing gun and am trying to save weight. I know there are a lot of factors in play as well but after doing a search I cant seem to find an answer. Thank you
     
  2. P KUNDA

    P KUNDA Well-Known Member

    Messages:
    121
    Joined:
    Feb 2, 2008
    A Slow or a Fast barrel

    Can have a big influence on the actual outcome, but under normal circumstances it should be anywhere between 60-80fps.

    Peter
     

  3. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

    Messages:
    2,612
    Joined:
    Mar 12, 2002
    If you are rebarreling anyway you may want to consider some other choices that do better in a short tube than the 7mm rem mag. 7mm's off the blown out '06 case do well with short barrels and you can equal the magnum in performance with less powder and recoil and brass is cheaper. Use a little faster powder that gets more burn in the short tube and you get a little more efficient cartridge. The short mag does fairly well in a short tube with a little faster powder. How much velocity you will lose is dependent on which bullet and powder you use. Heavy long range bullets need a lot of slow burning powder typically which need barrel length to burn or you watch your powder burn in a huge muzzle flash out the barrel which does no good. I have a 7mm JRS and the 7mm gibbs off blown out '06 cases and both will equal the 7 rem mag in a 24" tube with a smaller dose of faster powder.
     
  4. Boss Hoss

    Boss Hoss Well-Known Member

    Messages:
    1,843
    Joined:
    Nov 10, 2005
    To answer your question --- it depends on the powder. I have found and many have done testing to prove this --- there is no standard and it depends on the individual rifle, bullet and powder combination.

    Do some research on the net --- it is out there.
     
  5. little black 243

    little black 243 Well-Known Member

    Messages:
    74
    Joined:
    Feb 25, 2008
    Thank you for the replys
     
  6. yellowjacket

    yellowjacket Active Member

    Messages:
    25
    Joined:
    Dec 10, 2004
    The short answer would be perhaps in the 50 to 80 fps. range.