What round to use 375RUM or 378Weatherby

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by bigrich954rr, May 30, 2006.

  1. bigrich954rr

    bigrich954rr Well-Known Member

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    Trying to plan how to build my next gun. I know its going to be 375 cal. i know the 378 has better brass. but is there any draw back to this round. The action will be a bat repeater.
     
  2. ceg1963

    ceg1963 Well-Known Member

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    I like the .375 RUM. A great performer.
     

  3. sewwhat89

    sewwhat89 Well-Known Member

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    I would say the 375 RUM. Less hassle without the belt; not sure there is any game that can tell the difference between the two rounds.
     
  4. davewilson

    davewilson Well-Known Member

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    the weatherby will get you maybe 50-100 more feet of kick,i mean fps!
     
  5. bigrich954rr

    bigrich954rr Well-Known Member

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    I think ill do the RUM will i be able to get to about 3000fps with 300 gains in 28 inch barrel
     
  6. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    Probably not quite with the RUM cases but you will get close enough that you will never know the difference.

    I have developed loads for several 26" barreled 375 RUMs that topped out at around 2900 fps with the 300 gr pill. These were what I would call max load levels in these rifles. If you get a custom chamber you may ba able to handle a bit more pressure but not a whole lot.

    You will not see alot of velocity gain from 26" to 28" in the 375 caliber. Actually, I would guess less then 30 fps. I would personally opt for a shorter, stiffer barrel but it all depends on what type of rifle you are going to build.

    In the field and at long range, you will be hard pressed to tell the difference between a 375 RUM and 378 Wby, except on the recoil end of things. Course if you have a brake on the rifle neither are hard to shoot.

    The 375 bore makes the 338 bore look silly effiency wise. Do not think you need alot of barrel to get good FPS. You simply do not need alot of inches even with a 100 gr capacity in this bore diameter.

    Kirby Allen(50)
     
  7. Eaglet

    Eaglet Well-Known Member

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    I never paid much of a thought to the 375 RUM as a long range rig. I ran some comperisonS against my 300 RUM using 210 Vergers, BC = 0.640 and for the 375 RUM 300 gr. Barnes triple shock because of its high BC of 0.555. I am impressed to say the least. I'm using 2850 MV for the 375 RUM as you can see below. Here are my findings.

    [​IMG]
     
  8. Jon A

    Jon A Well-Known Member

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    [ QUOTE ]
    and for the 375 RUM 300 gr. Barnes triple shock because of its high BC of 0.555.

    [/ QUOTE ]
    You might want to hold off judgement until Barnes tests and gives that bullet an accurate BC, which should happen soon.
     
  9. Eaglet

    Eaglet Well-Known Member

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  10. Jon A

    Jon A Well-Known Member

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    I mean that number is going to change soon. It'll be more accurate once it does.
     
  11. bjlooper

    bjlooper Well-Known Member

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    Has anyone tried the 375 Weaver it is a 375-300 RUMImp.
    I belive you can get a extra 100 - 150 fps over the 375RUM.
    Dr B
     
  12. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    BJ,

    YOu will not get that much velocity increase. If you compare the 375 RUM to the 378 Wby in same length barrels, the MUCH larger 378 Wby will only get you 100 fps more velocity.

    The improved version of the 375 RUM may get to 40 to 50 fps more at the vary most. Variations in barrels will determine which would produce the most velocity, a standard or Improved 375 RUM. WHen the bores get this size, improving them, especially improving a RUM case will not get you much as far as increased performance.

    Kirby Allen(50)
     
  13. Hired Gun

    Hired Gun Well-Known Member

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    Whatever the 375RUM does the 378Wby does it better if balistic performance is a concern. The belt is not a hassle. Being it's going into a bat, I would look into a Kahn with Kirby. More is a good thing when your going medium. If I was doing up a Bat, and I sure wish I was, I would be all over the 338AM. I have buddy with one on order and we can hardly wait. I would park everything else and use it on everything. It makes the 375RUM look a little anemic. Maybe you could have the first 375AM. I'm sure it has been discussed. Just needs a little demand to make it happen.
     
  14. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    Hired Gun,

    Believe me, the 375 Allen Mag is sitting here in front of me on my desk on paper. This one has been just begging me to send the reamer print in for the build. With the right bullet, a 375 Allen Mag would give you everything the 338 AM would ballistically but with a significant increase in kenetic energy and frontal area.

    Right now the only thing holding me back is a viable bullet. By that I mean a 380 to 410 gr ULD RBBT. Unfortunately, not good news from Wildcat bullets on those dies though so for the time being we are leaving things on paper.

    No sence doing all the work to throw a 300 gr Sierra BTHP out there that will not even handle the impact velocity. SHE would be fast as hell though!!!.

    If there is interest there will be a 375 Allen Mag here soon. Again, it is my personal opinion that it would be a better round then even the 338 Allen Mag and I think the 338 is about "it" as far as ballistic performance is concerned currently, even including the 50 cals.

    Kirby Allen(50)