.338 RUM ballistic question

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by TriggBaker, Sep 5, 2013.

  1. TriggBaker

    TriggBaker Well-Known Member

    Messages:
    55
    Joined:
    Dec 2, 2012
    I'm trying to figure out the speed of my rounds, I don't have access to a chronograph and am trying to avoid buying one so I looking for some help. I have a .338 RUM 28inch barrel shooting a 200 grain Hornady SST with 98 grains of 4831sc. I'm hoping somebody has a pretty good idea what the muzzle velocity is. Thank you for the help
     
  2. ICANHITHIMMAN

    ICANHITHIMMAN Well-Known Member

    Messages:
    4,380
    Joined:
    Jan 31, 2008
    They cost 100$ from Brownells dude? If you cant swing that, use a friends, but in all honesty you don't need one. There are only two ways to get your dope and they both rely on the same method for 100% certainty.

    With the advent of modern ballistics software a lot of people seam to be under the impression that conformation of actual drops is no longer relevant. However that's a misnomer to say the least. Your going to have to go out and shoot your dope from zero to what ever distance you intend to shoot, then add the data to your ballistics calculator and adjust your muzzle velocity until your actual dope and the dope the calculator is giving you match. In a round about way this will give you what you asked for in your initial question.

    If you do acquire a muzzle velocity make sure you still shoot the drops to confirm and adjust the calculator to reflect your actual drops.
     

  3. J E Custom

    J E Custom Well-Known Member

    Messages:
    7,311
    Joined:
    Jul 29, 2004
    +1

    I have a chronograph and still have to shoot different distances to verify drop and BC of the bullet.

    The bullet makers BCs are seldom perfect (Always on the high side)

    Shoot your load @ 100, 200, 300, 400, 500, and 600 yards using the same aim point(I use a large piece of paper with the aim point at the very top and start shooting 3 shot groups at 100 yards.
    then I back up to 200 yards and repeat the process. Continuing one to 600 yards.

    You can then measure the drop at each distance and if you use this drop and compare it to your loading manual you can get close to the velocity of your load. Velocity may vary due to the actual
    BC of your bullet but it will be close.

    I use my chronograph more for load development than anything else.

    J E CUSTOM
     
  4. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

    Messages:
    6,848
    Joined:
    Jun 12, 2004
    Invest in a chrono. There is NO WAY for anyone to estimate what your rifle is producing for velocity so without actually KNOWING, your guessing and that's not good.

    As mentioned you can test your drops over many ranges and reverse engineer your velocity but you can save ALOT of time and shooting if you get a chrono. For the price of two boxes of factory 338 RUM ammo or two boxes of some top end bullets for reloading you could own a chrono. No real good reason not to have one and a lot of great reasons TO own one.
     
  5. angus-5024

    angus-5024 Well-Known Member

    Messages:
    1,132
    Joined:
    Jan 22, 2008
    I agree with the others, get a chrono.

    On the other hand, I would think your load will be pretty fast. somewhere around 3500Fps. With 210 TTSX's I got 3390fps and I think they have a longer bearing surface.
     
  6. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

    Messages:
    6,848
    Joined:
    Jun 12, 2004
    I would agree, with that bullet weight you will be quite fast, I would recommend what shots your taking if your hunting heavier game such as elk. At close range, your penetration may not be all that impressive on hard impacts such as a shoulder knuckle.

    For deer and such it would be perfect but you may still see some very dramatic bullet expansion.

    If you want to get really high velocity and want to hunt heavy game at closer ranges, you may want to look at some of the Barnes TTSX bullets. THey will generally take any velocity you put to them and still get the job done on the terminal end. Not the best for long range hunting but neither is the 200 gr SST.

    Just a side recommendation.