Best bullet for long-throat Accumark 300 win mag

Discussion in 'Reloading' started by LRHChinook, Apr 20, 2013.

  1. LRHChinook

    LRHChinook Member

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    I'm having trouble finding an accurate bullet for my Weatherby Accumark 300 win mag. Bergers (165 gr and 185 gr) don't work at all and Berger says it's probably due to the Weatherby long throat. Weatherby suggests a flat base bullet. I've tried Sierra Pro Hunter 180 gr with only limited success.

    Nosler partitions have a mostly flat base; how about them?

    I've finally drawn a tag for a NM elk hunt so I need to get serious... Thanks
     
  2. MudRunner2005

    MudRunner2005 Well-Known Member

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    Weatherby's have free-bore for a reason. You will never be able to seat that bullet properly and have it be touching the rifling. Tried it with my .257 Wby....Wasn't happening.

    So I just seated them at the maximum magazine length where they would barely fit, but still feed reliably as a repeater for hunting, and I let it ride.

    Flatbase or boattail makes no difference to how the rifle likes it....That helps determine how effective the bullet will remain stabilized when in flight. The boattail bullets help create a more turbulent wind drift behind the bullet because of it's shape, which 1) helps stabilize it, and 2) helps it be more aerodynamic and efficient at cutting through the atmostphere.

    All I shoot are boattail bullets.

    You should try the Berger VLD's. Try the 168 and the 210's. I have had excellent results with the 210's from my .308 Win, and from my buddy's .300 WinMag that I load ammo for. I loaded some for my other buddy's .300 Wby Mag, but he hasn't been to the range to shoot yet...
     

  3. LRHChinook

    LRHChinook Member

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    I've tried the Berger VLDs 168gr using 78.5 gr of H1000. My groups (from a bench rest) were all over the place. I use an electronic scale to weight every powder charge and am using Swarovski optics. I did what you did and seated the bullets so they just fit in the magazine.

    Can you suggest a different powder? I'd to get these Bergers to work... :)

    PS. Berger suggests (among many) 66.5 gr IMR-4350 or 67 gr H-4350. What is the difference between IMR and H with the 4350? I have some H but no IMR...
     
    Last edited: Apr 20, 2013
  4. MudRunner2005

    MudRunner2005 Well-Known Member

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    Berger says 83.0gr is the max load with the 168's, so I'd try working my way up. Start somewhere in the middle, but Weatherby rifles with the freebore tend to love hot loaded ammo. So, try about 80 and work up to 83 in 0.5gr incriments.
     
  5. LRHChinook

    LRHChinook Member

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    MudRunner,

    You responded whilst I was typing... Can you comment on my 4350 question? Thanks
     
  6. MudRunner2005

    MudRunner2005 Well-Known Member

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    I haven't used any IMR powders, but have been thinking about some IMR 7828 SSC, as it can be used in a huge array of different calibers, just like H1000 can.

    H1000 has become my favorite magnum powder, I also use Alliant Reloder 19 & 22, and am trying to get my hands on some Retumbo and Alliant 25 at the moment. But can't seem to find any...

    I have found H1000 is not a very temp-sensative powder, like alot of them are. And it works great in my .257 Wby, 7mm RemMags, and 7mmSTW. So, I keep a fair bit of it on-hand, since it has worked so well for me in so many different calibers.

    I wish I could comment on the IMR powders, and do hope to try some 7828 SSC soon. If I get a chance to, I'll let you know my findings.
     
  7. LRHChinook

    LRHChinook Member

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    I have two canisters of RL-22. I think I'll try some recommended and max loads of that (73.3/77.6) with the Berger 168s. Also the same for my H4350.

    As I said, I also have some Berger 185 VLDs. Care to speculate on whether these will shoot better in my Accumark than the 168s? I failed to record my group sizes with the 185s when loaded with 75.5 gr of H1000 but they must have been bad... Maybe I'll give them another chance with RL22 and H4350... if you tell me Bergers may actually be OK in my long-throated barrel..:)
     
  8. MudRunner2005

    MudRunner2005 Well-Known Member

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    I haven't shot any of the 185's, so I don't have any idea how they might react, or what might be better with what powders...
     
  9. TOM H

    TOM H Well-Known Member

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    I think Wby would build a SAAMI spec 300mag and not have the long wby freebore.

    I tried to find same article that was posted here but here it is from another site
    Berger Tips for Loading VLD Bullets « Daily Bulletin

    The Wby 300mag has a 1/10 twist barrel that twist may effect the Berger VLD bullets and you may do better with a standard type bullet. what you should ask Wby is what ammo they run accuracy test in that rifle. I have never shot the Berger 185gr in a 1/10 twist barrel been shooting them in a 1/12 twist 30 cal mag.

    here is the bullet range that Wby offers for the 300Wby
    Berger Tips for Loading VLD Bullets « Daily Bulletin

    Well good luck
     
  10. RTK

    RTK Well-Known Member

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    Why would they cut the throat long if it is a 300 win mag??? My 300wm (1/10 twist) likes the berger 215's and imr7828....
     
  11. extreme

    extreme Well-Known Member

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    Barnes or Nosler or Hornady are what will take your troubles away and Shit can
    the burgers ,,,that's why weatherby doesn't use them in there ammo line.
     
  12. cwinner

    cwinner Well-Known Member

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    my experience with the 300WM suggests that RL 22 would be a good choice for these mid weight range bullets, H1000 does a little better with the heavies over 200grains. Have you measures the throat length to see if you have any freebore? I would also reccomend changing a scopes from a know shooter to verify that it's not the scope, don't believe for a second that just your scope is a swarovorski that its a perfect performer.......it's one easy thing to check off the list and can save you lots I components.
     
  13. Broz

    Broz Well-Known Member

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    The Accumark chambered in 300 win will not have the free-bore that the Weatherby chamberings do. So all that about flat based bullets and Wby's is out the window. I would get away from the small offerings and load some 210 or 215 Berger's in it with H-1000. The fact this is not chambered in a Weatherby caliber takes away all and anything about what brand rifle it is or what bullets Wheatherby uses in their factory ammo. It is a 300 win and once the bolt is closed it is all about your load. I have yet to see any 300 win that didn't like 210 or 215 Bergers and H-1000 with a Fed 215 M primer.

    Cwinner also brought a very important thing up. Check the scope and double check the mounts!!

    Jeff
     
  14. cwinner

    cwinner Well-Known Member

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    I agree with Broz that most 300WM will devour 200+ bullets and H1000, for reference I recently re-barraled one of mine with a 1:10 twist Schillen tube and it loves 75.0gr H1000 with the 230gr OTM Tatical Berger bullets Fed 215 M primers into one ragged hole......I plan to try the 215's someday when I can find them. A key is finding the seating depth, mine likes the 230's on the lands but jumping the 210 VLD's .080" makes them shoot. That's why it's important to determine seating depth, I run the searing dept test liked earlier and can swear it works, if your scope is good:D