338 Ultra Mag vs 340 Weatherby

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by tfjar15, Jul 20, 2006.

  1. tfjar15

    tfjar15 New Member

    Messages:
    3
    Joined:
    Jul 20, 2006
    I need some expertise in the reloading aspects or benefits and drawbacks for these two calibers: 338 Ultra Mag and 340 Weatherby. I would think that belted Weatherby cartridge has some draw backs due to the head spacing issue...i.e.….little more finicky on accuracy, pertaing to the double radii. I am looking on sending this gun out ASAP to make this year’s elk season. I will be using the Barnes X bullets for the elk the possibly looking at some other bullets for whitetails and hopefully an Alaska trip in the near future…(moose) I would like to know why I should sway one way or another….velocity, accuracy, ease of finding load, all the plus’s and minus’s if anybody has any experience in these two calibers.
     
  2. sambo3006

    sambo3006 Well-Known Member

    Messages:
    1,343
    Joined:
    Jul 30, 2004
    I don't have experience with the 340 wby but I have a 338 RUM, as do several of the guys here at LRH. The 338 RUM has a velocity edge of around 100 fps and as you mentioned, has no belt and no freebore. It is capable of sterling accuracy. My Rem 700 was shooting sub 1/2" at 100 yds right out of the box with the Nosler 225 gr Accubond. Brass is cheaper for the RUM. Having said that, there are several guys who shoot the 340 Wby and love it. Practically there is little difference in these two rounds. It probably boils down to personal preference.
    A case can be made for the 300 RUM, which is quite popular among the long range guys. It is capable of shooting the 200 gr Nosler Accubond at 3200 fps out of a 26" barrel, and has an outstanding (for big game bullets) ballistic coefficient of .588 . This compares to 3100 fps for the 225 gr AB out of the 338 RUM with a BC of .550 . The 300 RUM has a slightly greater case capacity than the 338 RUM, and brass is available from sources other than Remington if that matters to you.
    You should get lots of input on this topic from guys with lots of experience. Welcome to LRH and good luck this fall!
    Sam
     

  3. Boman

    Boman Well-Known Member

    Messages:
    1,067
    Joined:
    Sep 25, 2002
    Both my father and I have .340wby's. We love them. His is a Wby Accumark and mine is full custom job on a Rem 700 action. Both of ours are extremely accurate. Dads shoots about .70moa when he does his part. Mine is about .4-.5 when I do mine. We both shoot Barnes Trip shock bullets. I have never found it difficult to load for at all. The brass last for about 6-7 loadings, but we load ours pretty hot.

    I really think it comes down to personal preference. Most guys chose based on the factory rifle that chambers them. But since your having yours built you could go which ever way you want.

    If I wanted a long range elk gun and was building it now. I'd go for a Shawn Carlock .338 Edge.

    Right now my .340Wby is an ultralight weighing 5.75lbs without scope. And I love it for close up shooting and out to 700yds. Its my main hunting rifle and my backpacking rifle as well.

    Pick what excites you. Good luck and have fun! /ubbthreads/images/graemlins/grin.gif
     
  4. Eaglet

    Eaglet Well-Known Member

    Messages:
    2,779
    Joined:
    Feb 2, 2005
    Boman,

    [ QUOTE ]
    Right now my .340Wby is an ultralight weighing 5.75lbs without scope.

    [/ QUOTE ]

    Tell us, does it have a muzzle break? I feel it doesn't, I'm I wrong? If I'm right after you shoot it from the bench 5 times for how long dol you put hot and cold patches on your shoulder? /ubbthreads/images/graemlins/smile.gif It's gotta hurt!!!
     
  5. remingtonman_25_06

    remingtonman_25_06 Well-Known Member

    Messages:
    2,030
    Joined:
    Jun 4, 2003
    No kiddin, I'm thinking the same thing. Im thinking maybe he has it ported to keep the weight down.? Theres no way you could get me to touch that off! I thought my 300 RUM with 220g's at 3000fps out of a 9.5lb rifle was quite a bit.
     
  6. RDM416

    RDM416 Well-Known Member

    Messages:
    700
    Joined:
    Jan 31, 2005
    Both are great rounds, and you cannot go wrong with either. I have two Weatherby's and like them, so I am not a Wby basher. But that said, I would go with the 338RUM. Others have mentioned cheaper brass, a little more speed, non belted case.........all are positives. I have a 338RUM in an HS-Precision and it shoots great.

    The 338 Edge is also a good improvement over the RUM but you have to fire form brass. Not a real big deal, but worth considering. It will get you some more speed though and that is always a good thing /ubbthreads/images/graemlins/grin.gif

    Last, put a muzzle brake on that thing!! You will not regret it. For long range shooting you will need to be looking at the heavier bullets 225's and 250's. (I like 250grn Sierra Match Kings myself) With those larger bullets and a full load of powder you will get a real wake-up call if you don't have a brake /ubbthreads/images/graemlins/shocked.gif
     
  7. Boman

    Boman Well-Known Member

    Messages:
    1,067
    Joined:
    Sep 25, 2002
    Hey Guys,
    Yeah my rifle does have a muzzle break on it. I've shot it without and lets just say it was... unpleasant. All up with a scope and loaded its right at 7lbs.. I'm changing the scope out to an IOR so that will increase the weight to about 8lbs. Still not much.
     
  8. davewilson

    davewilson Well-Known Member

    Messages:
    2,634
    Joined:
    Feb 19, 2004
    RDM, you mention with an edge you have to fireform brass. my understanding is this is not the case.no pun intended. can you explain why?
     
  9. Wild_Bill

    Wild_Bill Well-Known Member

    Messages:
    744
    Joined:
    Sep 15, 2005
    Hi the 338 Edge is made by necking up a 300RUM to 338 with no other changes as the best of my knowlidge si it does not require fire forming any diferently than any other new case. If i was you i would look at these calibres in this order.
    1. 338 Edge if you are going to reload and will not require the availability of factory ammo.
    2. 338 RUM if you have to be able to use factory ammo
    3. 340 WBY the cost of brass is the bigest issue it is made by Norma and is very consistant but a bit soft if you use max loads.

    All of the above i do think you should hand load for anyway to get the best performance with you could not rely on going to a gunshop in the middle of no where and find a 338RUM or 340WBY there as they are not realy popular most places and only large shops would likely have a variety in stock. Also with the Edge youi can back the pressure doen a bit and still pass the velocity of the other two. If it is a custom barreled firle go this option. Now if you are looking to build a rifle i would look at buying a Sendaro II in any form of Ultra Mag send it to Shawn and have him true up the action fit a larger recoil lugg, muzzle break and barrel then sell the take out barrel. Also have him adjust the trigger and you could get an adjustable cheek piece and you would have an awsome rifle.

    Cheers Bill
    Australia
     
  10. jro45

    jro45 Well-Known Member

    Messages:
    158
    Joined:
    Dec 20, 2003
    I have the 338 RUM in 700 action 26" barrel. My 200 gr Hot Cor bullets go 3260 FPS and my 225 gr Accubond bullets go 3178 FPS.I use RL25 powder
    The 200 gr Hot Cor bullets shoot a 5/8" group at 200 yds and the 225 Accubond bullets shoot a 7/8" group at 200 yds.

    I have heard that the WBY 340 with a 26" barrel got real close to those FPS that the RUM can shoot.
     
  11. tfjar15

    tfjar15 New Member

    Messages:
    3
    Joined:
    Jul 20, 2006
    Thanks for all the good info, I have ordered the 338 RUM today, and waiting for its arival. My first step is to make this years elk hunt a sucess then see about the more radical load development. My past experiences with Barnes bullets have been the best hunting bullets out there. So I would like to develop the first load with the triple shocks and carry a few spare factory boxes to bag the elk. Then go for the long range dusted whitetail when I get back here to Texas. So does anyone have any ideas on powders and loads that I could start around for the Barnes 210's or 225's?
     
  12. sniper2

    sniper2 Well-Known Member

    Messages:
    948
    Joined:
    Jan 10, 2003
    For better performance get one of the smiths here to bump the chamber up to .338/300...I am talking about the larger bullets... /ubbthreads/images/graemlins/wink.gif
     
  13. Shawn Carlock

    Shawn Carlock Sponsor

    Messages:
    1,897
    Joined:
    Jun 11, 2007
    I have had good results with H1000 in the 338 RUM, it will be plenty full though.
     
  14. sniper2

    sniper2 Well-Known Member

    Messages:
    948
    Joined:
    Jan 10, 2003
    My .338/300 RUM will push 200 gr bullets past 3500fps with very little pressure sign, prefer the 250 SGK and 300 SMK...