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Weatherby freeboring

Discussion in 'Rifle Country' started by elktrout, Feb 1, 2013.

  1. elktrout

    elktrout Well-Known Member

    Weatherby has historically made their Mark V rifles in various non-Weatherby chamberings, such as the 30-06 and even the 300 Win Mag. Are those rifles freebored like their proprietary chamberings?

    If they are freebored, do normal reloads experience a velocity loss? Do you have to increase the powder charges to get back to typical velocities?
  2. Birdhunter1

    Birdhunter1 Well-Known Member

    I think the freebore exists only on the Weatherby cartridges but I could be wrong. I've got a mark V 7 Weatherby mag that of course does have a free bore but my dad has a 30-06 Mark V and I don't think it does.
  3. Ken70

    Ken70 Well-Known Member

    I thought they would pick up speed with the freebore. No resistance from engaging the rifling like a normal gun. Without the freebore, Weatherby's would be overpressure and damage the rifle.
  4. bobnob

    bobnob Well-Known Member

    Just how much is the freebore on a Weatherby chambered rifle?

    I have a 270 Win which still has about .1 freebore even when the bullet is seated to 3.4". How does that compare to say the 270 Wby?
  5. Strongbad

    Strongbad Well-Known Member

    The standard rounds will not have the extra freebore of the big Wby cartridges.
  6. Ken70

    Ken70 Well-Known Member

    I was reading about Weatherby in a Gun Digest and the number 3/4" of freebore sticks in my head. I've got about 40 Digest books and couldn't find the article. Wish they sold an index.
  7. hueyville

    hueyville Well-Known Member

    As Phil Sharpe and P.O Ackley both say. Free bore is just a cheap work around for a inherently over bored cartridge. If you know how to load meticulously, you can have a good smith shave the rear of the barrel or build a barrel up from scratch in .270 Weatherby with no free bore and it can be made to do some impressive work. It's all in your skill set at the loading bench.
  8. bobnob

    bobnob Well-Known Member

    Wow 3/4 inch! Now you mention that, I seem to recall reading that too.

    Huey, so what you are saying was freebore was a bit of a cheap trick to boost velocities? Sort of an artificial way to allow faster burning powders to be used?

    On what you wrote, I agree it would seem the 270 Wby has plenty going for it even without a lot of freebore.

    Thanks guys.

    - Bob
  9. moonzapa

    moonzapa Well-Known Member

    I own two Weatherby's, both Mark V's, in 280 Remington and .243 Winchester. Both have standard throats. Both are very accurate and my go to rifles for hunting deer, hogs, coyotes and bobcat.
  10. GooseGestapo

    GooseGestapo Well-Known Member

    The early Weatherby rifles had a long free-bore. 0.50" seems to come to mind, but could have been as much as 0.75".

    The newer ones have standardized on 0.375" or 3/8".

    It's not the accuracy handicap some imagine. Neither is it a "fix" for an overbore cartridge. It's a way to deal with possible pressure excursions due to high temperatures where some hunting with Weatherby cartridges occurs (S.W. USA, Africa, ect.). It also makes a top-end cartridge a 'little bit better', at least it did to Roy Weatherby when he was starting the company 60yrs ago. It made excellent sense back in the '40's and '50's. Not really neccessary now, but, thats part of what makes a Weatherby a Weatherby.....

    I have a Vanguard (not MOA model) and it has the 3/8" freebore. It too, is sub-moa accurate.
    Remember, they are HUNTING RIFLES, not target rifles.... anything better than 1.5moa is nice, but not neccessary...
    And, with RL25 and a Hornady 100gr SPT it gets 3,600fps+ and sub-moa even from a 24"bbl, so I don't really miss the extra 2" of barrel length...
    I just wish it'd had a better trigger. It took a $100 Timney trigger to "fix" it....
    Last edited: Feb 4, 2013
  11. Silent Sam

    Silent Sam Well-Known Member

    Cartridge Throat length (free bore)
    .224 Weatherby Magnum .162
    .240 Weatherby Magnum .169
    .257 Weatherby Magnum .378
    .270 Weatherby Magnum .378
    7MM Weatherby Magnum .378
    .300 Weatherby Magnum .361
    .340 Weatherby Magnum .373
    .375 Weatherby Magnum .373
    .378 Weatherby Magnum .756
    .416 Weatherby Magnum .239
    .460 Weatherby Magnum .756
    .30-378 Weatherby Magnum .361
    .338-378 Weatherby Magnum .361

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