7mm-300 Weatherby

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Jim in Cali, Nov 27, 2013.

  1. Jim in Cali

    Jim in Cali Well-Known Member

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    Ok I have a 300 that I cant' seem to sell so I am contemplating on just doing a re-barrel and the 7mm-300 looks intriguing, anyone shoot one of these? and can I get some details on loading techniques..ie two die set,trimming,fireforming if necessary?.
     
  2. B23

    B23 Well-Known Member

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    My dad had one built about 17-18 yrs ago. He had a Wby MkV 257mag that never shot to his liking so he sent it off to Howard Wolfe in PA. and he rebarreled it into a 7-300Wby mag. If I recall the 7-300Wby was kind of one of Howard Wolfe's specialties. I remember it shot really well. The 7-300wby is basically a twin to the 7STW.
     

  3. Chase Curtis

    Chase Curtis Official LRH Sponsor

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    I've spent some time (not a whole lot) behind a 284 baer... 7mm-300 wby imp.

    It was a pleasure to shoot and very accurate... I would build one...

    Neck it down.. Turn the neck ( or at least the one I shot was a tight neck) and shoot to fireform.
     
  4. Joel Russo

    Joel Russo Official LRH Sponsor

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    The 7-300 Wby followed the 6.5 Wby when long range hunting was born here in PA. One of the leading long range custom rifle builders was Howard Wolfe, and he specialized in chambering the 7-300 Wby.

    The simple solution is to take 300 Wby brass, neck it down to 7mm and be done. No fire forming is needed, and RCBS makes a FL size die and seat die set. The other option is to chamber a tight neck in the range of .312". I have owned both and see no discernible difference between turning necks and not turning necks because the drop in neck dimension does not warrant a must turn neck... I would suggest shooting bullets in the 162-180 grain range, so pick a twist that will allow stabilization, mine were 9 tw. After playing with the 7-300 Wby for a while, I started shooting the 7-300 Wby improved , aka the .284 Baer.

    I actually re-chambered a Hart barrel that was formerly chambered in 7-300 Wby. It is extremely accurate with the 180 gr bullets as Chase will tell you....killing PD's just shy of 1k yards in extremely windy conditions. If you choose this route, custom dies are a bit more expensive. I don't fret about fire forming like most of you, or buy into that talk about fire form loads before doing load development... All horse dung...load and start development.

    In summary, my personal experience is that the standard 7-300 Wby will suffice with a one step neck down and no neck turning. Plenty of bullets to feed it until you find the right combination.
     
  5. Jim in Cali

    Jim in Cali Well-Known Member

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    Thanks everyone.:cool:
     
  6. yobuck

    yobuck Well-Known Member

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    joel pretty much said all thet need be said about the 7x300 weatherby.
    i have 2 both built by howard wolfe. both have 9 twist barrels. one is a heavy
    sporter on a 700 lefty action and the other is a 30" hart on a single shot 40x.
    i use 162 gr hornadys in both with 81 gr 7828. according to my cheap chrony
    im very close to 3500 fps. 28" barrel is plenty for max performance.
    ive tried 175 smks and 180 bergers with both h 1000 and retumbo but have decided to stick with the 162s. (fire away berger lovers.) i consider about 1200 yds max for the cartridge. like joel i have better guns for longer shots.
     
  7. Mike mueller

    Mike mueller New Member

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    Great cartridge. I have used 7mm stw data to work up loads for it.It easier to get good quality weatherby brass than 7mm stw brass now. Necking down is simple.I've shot one for a while now and have had no issues at all.Remington 700 with 28'' hart barrel.