7mm caliber question

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Vleder, Oct 9, 2011.

  1. Vleder

    Vleder Member

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    Been thinking about building a long range (300 - 600m, yes I know not long range for you folks but plenty enough for me ;-)) hunting rifle (Springbuck to Eland) and target shooting a bit further. Want 7mm because of the excellent bullets available.
    My question is 2 fold, (and yes I have been chatting to vatious local experts as well but would like some other input as well);

    Caliber: want something that will launch the 168's (thinking 168 Berger VLD for target) at approx 2900 - 3000 without pressure, not eat the barrel in 500 shots, easy to load for (brass), good quality brass (Norma/Lapua). Same with 160's (Nosler AB 160 for hunting). Barrel will be 26", short/long action not an issue.
    Here is what I have gleaned from discussions so far (this is what I have been told by gunsmiths/comp shooters etc, so just bear with me):
    7mmRem Mag: great cal, but not inherently accurate enough? Rim on bottom issues. Just putting into QL the 168 S SMK and 61.0 gr S365 (South African powder) gives 2 918fps with 59 579psi, which is fairly high, does this seem correct? Hoped it would reach that at lower pressures.
    7mm SAUM: great but possibly a bit light for the speeds I want.
    7mm WSM: currently recommended as will do those speeds w/o any pressure, mild load will also not wear out barrel so quick, can neck down 300 WSM Norma brass, efficient round.
    I've read about 7/300 WSM?
    I'll be honest, 7mmRM will be easier re cost, brass prepping etc.
    Any other ideas?

    Bullets: target load either 168 gr Berger VLD or Sierra Matchking at 2900 to 3000 wherever speetspot is.
    Hunting load Accubond 160 gr at similar speeds. Will try to match the trajectory so be as close as possible to maintain zero with both, no adjustments. That way I can use AB to 400m and VLD further without having to adjust scope. If possible.

    Thanks in advance.
     
  2. 7mm Wsm

    7mm Wsm Active Member

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    I would go with a 7Wsm or a 7-300Wsm. Depends what gun you want to build. If its full Custom go with 7mm-300Wsm with Norma brass.
    I have a 7WSM full custom and i use blown out .270 Wsm Norma brass. I shoot the 168 Bergers with 930m/s (3050fps) out of an 24,5 inch 5R Border Barrel. Hell accurate!!
    regards from Austriagun)
     
  3. CRNA

    CRNA Well-Known Member

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    My 7RM does exactly everything you say you want. 168 Bergers/SMKs at about 2975fps. Great equipment availability. Solid .75moa.
     
  4. 4bycamper

    4bycamper Well-Known Member

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    I think you will find a lot of useful information at 6mm benchrest, here's the link:
    7mm Cartridge Guide

    I sure did and built myself a 7mm saum, 26 inch bbl, to get the same results you describe.

    Enjoy !
     
  5. Vleder

    Vleder Member

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    Anyone comment on the gunsmith stating that 7mmRM is not inherently accurate?
     
  6. 4bycamper

    4bycamper Well-Known Member

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    WHY do you think the 7mm Remmy Mag brass will be cheaper /easier to prep????


    Bullets: target load either 168 gr Berger VLD or Sierra Matchking at 2900 to 3000 wherever speetspot is.
    Hunting load Accubond 160 gr at similar speeds. Will try to match the trajectory so be as close as possible to maintain zero with both, no adjustments. That way I can use AB to 400m and VLD further without having to adjust scope. If possible.

    IN my 7mm saum, the 160 AB (3025 fps)and the 168 VLD ( 2973 fps)will not shoot to the same poi. The VLD is 10 inches lower at 500.
    Your mileage may vary.
     
  7. rscott5028

    rscott5028 Well-Known Member

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    7 Rem Mag will do the job without question. Lapua brass isn't available, but Norma is excellent.

    7WSM would be my second choice only because I've not yet owned one.

    You need to handload to achieve the results you're expecting. But, I like the option of using factory ammo.

    -- richard
     
  8. Vleder

    Vleder Member

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    4bycamper
    I would prefer less hassle re case prep (neck up/down, brass sorting, case thickness etc etc with the WSM brass), of the 7mmRM as you get Norma brass, basically load and shoot.

    Will definately handload whichever I choose. I am not an experienced reloader so I wold prefer the 7mmRM as the 'smith also has the reamer, actions etc at hand. Opting for the WSM's and I will have to get reamer, brass prep, etc which makes it more expensive and time consuming. But (contradictingly so) I would also like to have the most accurate round within these parameters...so I guess the question is if the 7mmRM is inherently accurate. I have read many articles on the 'net and there seems to be no firm conclusion to the fact other than minor issues with the belt aligning with the bolt face for the belted cases. Other than that the 7mmRM seems to be an accurate round and the downrange accuracy seems to be more dependent on the components and the person behind the rifle.
    Would that be a fair assumption?
     
  9. CRNA

    CRNA Well-Known Member

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    I was just shooting my 7RM at 700 yds the other day and it was pretty darn accurate. I wouldn't put much stock in the "inherently inaccurate" statement if I were you.
     
  10. Forrest Ebert

    Forrest Ebert Well-Known Member

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    While the calibers you have listed and others are quite good you have left out probably one of the best ones and that would be the 280 Ackley Improved! I shoot the 7Rum as well but the 280 AI with a charge of 63.0 grains of Retumbo and the 168 berger Hunting VLD chrono's at 2950 fps and is quite accurate and devastating on game! I do have other loads that push this bullet faster and as accurate but that is in my platform and don't know if it would be too much for another but you can get it to push that bullet into the 3000 range easily! The 7Rum . I like with the 180 grain and heavier up too 200 grains.! The WSM is confined to COL. which limits it if you are not single shot loading. My 280 AI has a 26" tube 3 groove 1:9.5 twist barrel on a blue printed and squared Rem. action. good luck in your search.
     
    Last edited: Oct 11, 2011
  11. Vleder

    Vleder Member

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    Incidentally the gunsmith I usually use (and trust) immediately suggested 300H&H for my purposes. Easy to load, long brass life (Nosler Custom brass), low preceived recoil, 2900 - 3000fps easily with 168 - 180grainers....and very accurate.
    Just a thought....although bc not as good for the .30 cal 168 to 180 grainers....
     
  12. 4bycamper

    4bycamper Well-Known Member

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    And there is the winning shot.

    Having loaded and hunted with 3 7mm mags (RM, WSM, SAUM), I'll venture a guess that there is little difference between them. Perhaps to the hunter, the wsm /saum will give you one inch more barrel for the same length rifle, if that matters. So it boils down to shooter's choice.

    I did not use any different procedures loading the 3 7mm mags. Nor did I experience any unusual problems with any of the brass. COAL is something to watch with any of them. And I weight-sort brass, making a batch within 0.2 grams. This seems to help shrink my groups some.

    So I get your 7mm RM and suggest Ramshot Magnum and H 1000.

    Enjoy
     
  13. rscott5028

    rscott5028 Well-Known Member

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    A well built 7RM will consistently shoot sub-MOA to 1k subject to the shooter's ability to compensate for wind. It will do the job in spite of any challenges that some shooters complain about with respect to belted cases.

    With a 1:9" or 1:9.25" twist, it'll shoot some very high BC bullets such as the 180g Berger.

    These have enough energy to take Eland at fairly long range for which sub-MOA will suffice. If you really want to stretch your limits on Eland, you might try a big 338.

    As for Springbok, it is accurate enough to take them about as far out as you'll be able to range them. It would be tough to range one accurately at 800 yds on flat land. And, you've got maybe an 8" oblong kill zone. 500-600 yds would be more reasonable for a laser rangefinder to get a reading.

    Ranging and wind will be your nemesis. ...not the cartridge or belted case.

    -- richard
     
  14. Jerry M

    Jerry M Well-Known Member

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    I have hits on steel out to 1175 yards with my heavy barreled 7 mm Remington Magnum. If put together properly, it is plenty accurate. Factory ammunition is also available in Maryland through Northern Quebec where I frequently hunt.

    I have to disagree about the long brass life in the .300H&H magnum. I am only getting 3 - 4 reloads out of WW brass, in this caliber. There is a tremendous amount of stretching in this caliber, which I attribute to the extreme taper of the case. Now they feed and eject like melted butter, as there were originally designed to do; so many years ago. Don't get me wrong, it is a very efficient cartridge, just not the best for case life.