284 winchester Improved Brass - Your recomendations please

Discussion in 'Reloading' started by Jeremy, Sep 12, 2008.

  1. Jeremy

    Jeremy Active Member

    Mar 12, 2008
    I'm building a new rifle with Lawton 400x action and Lilja Barrel a 284 Winchester Improved. Along with my gunsmith we'll design a chamber reamer with a 40 degree shoulder angle (instead of original 35 degree) and less body taper, approximately .010" (instead of original .025" of body taper). Essentially an ackley improved design.

    The reason for this round is to ease in the extraction of fired case (similar to the 284 Shehane) and split the difference between the 7mm-08 and 7mm WSM. With a 28" barrel and Reloader 17 I'm hoping to get a 180g. Berger VLD moving close to 3000fps.

    Would you choose to fireform Winchester brass or neck up 6.5-284 Lapua brass? On the 6mmBR website (260 Ackley Case Forming) a tech article where the author was fireforming 260AI brass from necked up Lapua 243 winchester brass. He was running into donuts being formed at base of neck. Perhaps using winchester brass that does not require necking up would eliminate this donut problem.

    Your thoughts on brass selection please.

  2. uncleB

    uncleB Well-Known Member

    Aug 19, 2005
    This is just my opinion and you can take it for what it's worth.

    I have more wildcat and improved calibers than I do standard calibers, with that said the LAST case I would improve is the 284 Winchester it already is "essentially an ackley improved design" doing it again is not worth the trouble, you could gain more by going to a longer barrel.

    If you are thinking this will ease extraction Bill shehane has you overly enthused.

    as far as brass neck-up 6.5x284 Lapua (no-brainer).

  3. Varminator 911

    Varminator 911 Well-Known Member

    Dec 7, 2007

    Don't see how you are going to be near 3000fps with a 180 Berger. Nosler lists top velocity in 284 with a 175 partition at 2714, 280AI at 2858, and 7mm WSM at 2951. You have more barrel but a slightly heavier bullet. Seems to me you will have very short case life at 3000fps.

    I've got a 7mm-08AI, true only a 23 inch barrel, but 3000fps with a 150 gn would be a very stiff load. More than I'd want to shoot unless this R17 is some magic potion.

    I think even the 168 Berger at 3000fps would be pretty hot. But you know what, that 168 Berger at any where near 3000fps is a pretty good long range load.

    Good luck!!
  4. TOM H

    TOM H Well-Known Member

    Dec 24, 2001
  5. JeffVN

    JeffVN Well-Known Member

    Mar 19, 2004
    +1 there are multiple articles on the .284 at 6mmbr.com., if you look iin the Forums, you'll find some load and accuracy specific data too. More then one shows the cartidge capable of 2,900+ fps when using a 30-32" barrel and pre-RL-17 powders, specifically H4350 and H4831. If you are looking for 2,900 and are willing to use a 30-32" tube, you don'te really need the AI version.

    I do like your thinking, though. If you look at teh 7SAUM, its going to be pretty close to your .284AI in capacity, and I know its capable of 3,000+, have seen one up close shoot less wind and less elevation that I run in my 7WSM.

  6. joeyb

    joeyb New Member

    Jan 29, 2009
    jeremy, i just had a .284 built and I'm easily running 180 bergers at 2900 -2950 with a 26 inch barrel and reloader 17. I agree that improving the .284 is unnecessary. Just set it up on a full length action, so you can seat the bullet out properly and get the full potential of the case. I started out with Norma brass, and regret it. A friend gave me a handfull of the lapua, and it seems a lot stronger, (almost 3000fps with very little pressure sign). good luck
  7. eddybo

    eddybo Well-Known Member

    Jan 5, 2007
    Hmmm I think I would just open the bolt face and build a 7WSM rather than building a wildcat that is not going to give you any substantial performance increase. Do not get me wrong I love the AIs and most wildcats, but this one just leaves me thinking WHY?
    Assuming your purchasing a reamer and custom dies, with the money your going to pay for a reamer and dies you could have the bolt face opened. Or at least you could use it to pay for 1/2 the price of a new bolt from lawton. Having 2 bolts would also open up a lot of avenues if wanted to make the gun into a switch barrel. Just MO
    Last edited: Jan 29, 2009