375 rum custom build options/ideas??

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by 500mag_guy, Sep 11, 2013.

  1. 500mag_guy

    500mag_guy Well-Known Member

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    Alrighty guys I've got a Remington m700 lss 375 rum and I'm looking for ideas on how to set it up. I'd like a long heavier contour barrel that will do well with the 350gr pill range. Plan to single feed.

    Looking to use it for extreme long range.

    How would you set it up? Keeping it pretty open to get lots of ideas please!! Think of it as a free build only boundrys are .375 cal and a Remington m700 action! Lol

    Thanks in advance for your help!
     
    Last edited: Sep 11, 2013
  2. Tikkamike

    Tikkamike Well-Known Member

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    well well well, look who couldnt stand to leave well enough alone haha. as you know mine is getting a #5 Benchmark as we speak. its actually a 5.5 the muzzle is .712 finish at 26" I went with a 10 twist in the 5C rifling and I think itll be about right for the 270TSX which is my primary bullet but also i have enough twist if I wanna play with the big CE bullets. I think if you are going to be packing it I wouldnt go much heavier than about a #6 26-28" long. and I think the 10 twist should do anything you want to do. I am very interested to see what you decide on. then at the end we can compare notes.
     

  3. 500mag_guy

    500mag_guy Well-Known Member

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    Haha I was wondering how long it would be before you found this thread! Did you decide to go with another rum or the h&h?

    It's kind of all up in the air right now. I'd think 28-30" would be handy. And who knows maybe a 375 rum improved?

    I don't know every time I go into the safe and see it there I just imagine all the possiblities and potential for this caliber beyond a stock rifle!
     
  4. Tikkamike

    Tikkamike Well-Known Member

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    I came to my sences and went with the RUM... no reason not to. I like your thought process, however I have to say im not a big fan of the improved for the reason of the rum case is already pretty straight walled any straighter with a hot load you have very little taper to aid in extraction... just my thoughts. However my build is geared more toward hunting where as yours sound like its more like a long range target/ hunting when you will likely have a lot more time on your hands.
     
  5. 500mag_guy

    500mag_guy Well-Known Member

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    Glad to here you stuck with the rum.

    And you bring up a very good point with the improved.. I have a good feeling that with the right length barrel the rum will produce the velocity.

    What do you think a guy could get for velocity out of a 28-30" tube?

    Mainly hunting but I just won't walk 10 miles that day lol
     
  6. Tikkamike

    Tikkamike Well-Known Member

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    I dont know but the 26" has been nothing short of impressive... i guess 75-100 fps per inch
     
  7. 500mag_guy

    500mag_guy Well-Known Member

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    I'd probably have to have close to a 30" tube to get 3k then ya think ?
     
  8. Tikkamike

    Tikkamike Well-Known Member

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    I would ask someone with exball.. at somepoint adding barrel will be a moot point
     
  9. 500mag_guy

    500mag_guy Well-Known Member

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    Gotcha. That's why i asked how others would build it because I have no clue what the Optimal berrel length would be for that caliber.
     
  10. MontanaRifleman

    MontanaRifleman Well-Known Member

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    Maybe Kirby will jump in, but in the mean time I recall reading him to say that there is not a lot of gain in a longer barrel with 375 as it is not very overbore.

    If you are dead set on the Rem 700 action, disregard the following.

    If you are looking for a carryable ELR 375, I would go with a Lapua Imp version or Kirby's 375 Allen Express. Advantges....

    Much better brass
    More case capacity
    Shorter COAL to allow long high BC bullets seated efficiently and able to fit in the magazine for a repeater.

    And if going with the Lapua, I would go with a good custom action.
     
  11. 500mag_guy

    500mag_guy Well-Known Member

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    Mark, to hear from a couple builders would be much appreciated!!

    I think I'd really like to stick with my 700 action.

    I really appreciate your replay and all your info.

    Just would love to get them 350gr pills moving a little quicker :D
     
  12. Tikkamike

    Tikkamike Well-Known Member

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    The 700 action and the Remington brass available for the 375 will not come up short. The brass will need a little extra prep but in my experience the 375 rum is some of The better brass Remington made. The ultra mag case is an amazing building platform so don't be shy about using your current action
     
  13. MontanaRifleman

    MontanaRifleman Well-Known Member

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    Mike, I am in no way trying to dis the 375 RUM, but in an attempt to be objective, my opinion is the Lapau case offers a lot more for reasons stated. More powder in a shorter case with superior brass. I've never worked with 375 brass but the 300 RUM brass looses it's pockets in about 5-6 firings at max pressures. Maybe I'm wrong, but I'm guessing the Lapau quality and strength exceeds the RUM's. More powder will mean more velocity and a shorter case means a shorter magazine friendly COAL. All plusses

    Mag guy, You could build the Lapua on the 700 but with the bigger bolt face you would probably be pushing it to close to its limits. I'll let the smiths comment on that if they jump in. I know with my 300 RUM build I replaced everything on the 700 donor except the receiver itself. The 375 RUM is a good cartridge but the Lapua will get you farther down range.

    As for projo's, you might consider these...

    https://cuttingedgebullets.com/cgi-bin/commerce.cgi?preadd=action&key=MTH_L350

    They have a little higher BC than the SMK's and you will likely be able to get them down the bore quicker because of their bore riding design.

    Good luck with your project!
     
  14. 500mag_guy

    500mag_guy Well-Known Member

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    Mark,

    We are talking about the 338 lapua mag correct?

    If so I've already got one of them puppies all done up.gun)