338 Ultra Mag

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by JohnH, Dec 22, 2003.

  1. JohnH

    JohnH New Member

    Messages:
    1
    Joined:
    Dec 22, 2003
    New Gun:
    I have not reloaded for some time and I am not up to date with all the info concerning this new firearm. Could some one please help me on this, bullets, powder, best ballistics, and any and all help will be a help. I live in Alaska, so I wanted a gun to cover all game, deer, caribou, blck bear, moose, elk and the brown bear, so the bullet start @ 160 and go to 300, so ive not found to much on this caliber yet and will await some ones comment .The help would be appricated.
    Thanks, JohnH
     
  2. jro45

    jro45 Well-Known Member

    Messages:
    158
    Joined:
    Dec 20, 2003
    Well John I use H1000 powder and got my load information from accuratereloading.com hope this helps you out.
     

  3. DANTEC

    DANTEC Well-Known Member

    Messages:
    390
    Joined:
    Jul 6, 2002
    338 cal is very flexible and a evry good caliber xcept in Africa where seely regulation in most country allow only caliber bigger than 375 !!!!even if your load is anemic !!!

    210 Nosler in light side can do the job on most species

    275 bullet weight as Speer GS is good for heavy game

    if you reload you can try to match two trajectory specialy if heavy bullet are use only in short range , I have never be in Alaskan ( I wish but need time ) but pictures doesn t look as AZ desert so open long range shooting seem difficult so that better to try to reach good balistic up to 300 meters only

    good shooting

    DAN TEC
     
  4. JMac

    JMac New Member

    Messages:
    4
    Joined:
    Jul 18, 2001
    I have two 338 RUMs and use a 250 grain bullet( Nosler Partition or Hornady SP) and either 91 or 93 grains of Reloader 25, set off by a Federal Large rifle magnum primer.

    Sorry I never did much work with lighter bullets.

    Joe.
     
  5. Mark_in_utah

    Mark_in_utah Well-Known Member

    Messages:
    71
    Joined:
    Jul 30, 2003
    My .338 RUM likes a 250 grain Gameking on top of 83.2 grains IMR4831 and CCI 250 primers. Got a 9/16" pattern, which is a ragged hole with this guy. The 225 grain Accubond couldn't do much better than a 7/8" pattern at 3054 fps using 91.4 grains of WC852(s). I want to try a 250 grain Partition and MK's to see how they'd do.

    Mark in Utah
     
  6. Mark_in_utah

    Mark_in_utah Well-Known Member

    Messages:
    71
    Joined:
    Jul 30, 2003
    As an addition:

    My gun did NOT like 200 grain Speers, or 225 grain Hornadys. It seems happier with heavier bullets.

    Had some severe fouling problems and had to fire-lap the barrel, but that's a whole different thread....

    Rem 700 LSS with a Vais brake, pillar bedded.
     
  7. Guest

    Guest Guest

    I'm wondering how hard is it to get used to the recoil of .338's this big? I love the .338 Lapua and am looking at building one on a .338 Ultra Mag Sendero. What barrel length should I go for?
     
  8. Mark_in_utah

    Mark_in_utah Well-Known Member

    Messages:
    71
    Joined:
    Jul 30, 2003
    Recoil first - it's exactly double that of a 7mm Rem Mag. You can either create a heavy gun that tames the recoil, or put a brake on it, or do both!

    As for the barrel length, Remington puts a 26" barrel on their RUMs, and I suspect that something more like a 27" or 28" barrel is in order (minimum length). I've heard of some people putting even longer barrels on them with good results. The heavier the bullet you plan on shooting the more improvement you'll get with a longer barrel.

    Sounds like you're building a hunting rifle. Anything longer than 26" will do pretty good.

    Mark in Utah
     
  9. alaska

    alaska Well-Known Member

    Messages:
    619
    Joined:
    Feb 1, 2010
    I have both the Lapua and Ultra Mag in 338

    My ultra mag is one of the Rem 700 XCR2
    The 26" is great but the Rem stock had to go........replaced with a HS Precision.
    I also sent it off to Mag Na Port for a port job instead of a brake......that is hard on the ears. Sure took the muzzle blast out of it.
    The trigger replaced it with Timmney Trigger and put a M16 extractor on it.

    Installed a HS Precision Detachable Floorplated on it.

    She wears a Older Redfield ILLUMINATOR Accurange 3x9 scope in Redfield Rings and Bases.

    I reload for the my 338 RUM using 230gr Fail Safes and 93.0 of IMR 7828 in R-P cases with CCI 250 primers and 250 Sierra GK with 92.0.

    Sure is a good shooter..........a lot of thump most excellent for moose past 500 yards.
     
  10. Plinker147

    Plinker147 Well-Known Member

    Messages:
    166
    Joined:
    Feb 7, 2015
    I load 250 gr accubonds or Berger in my 338RUM built on rem 700 action. With 26 inch barrel I get about 2970 with R25. I think the 250gr is the best fit for the 338 Rum in terms on speed and down range punch. The 300 gr will take over around 1000 yds. As stated early to get best out of the 300gr you need a 28-30 inch barrel. With a muzzle break its not bad to shoot, i wouldn't want to shoot one without a break
     
  11. blackaj

    blackaj Well-Known Member

    Messages:
    206
    Joined:
    Jun 4, 2010
    If you or any one is interested I have a 700 XCRII that I am going to convet to 28 Nosler. I am selling the 26 inch factory barrel with a brake (140) rounds through it, 300 count of 230 grain berger elite hunter bullets, RCBS Dies, and 96 count of Remington cases (70 of them twice fired, the other 26 once fired).
    send me a PM if interested.