300WSM question

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Armored Transport, May 20, 2013.

  1. Armored Transport

    Armored Transport Well-Known Member

    Oct 26, 2011
    I have a friend that is building a 300wsm on a long action and is setting up the chamber to be able to seat the bullits ( 215-230 Bergers ) real long. He says this will increase case capacity to be able to meet or even surpass 300WM performance at long range.My friend is very smart and a real fine smith but I know he has not personally done this before (more of a bench rest type/hunter). I am not real in the know about this type of thing and I would like to know if this makes much sence to you guys that are, Thank's for your input.........gun)
  2. winmag

    winmag Well-Known Member

    Dec 23, 2009
    Yep, you'll gain enough to take advantage of newer powders, & not be running compressed loads.
    As long as its throated long, & has a long enough pipe.

    *but, you could always do the same thing to a 300 Win & beat the WSM again because of the larger case capacity.

    In the end both cartridges absolutely kick @$$!

    I built my 300 WSM on a long action Model-70 Win, with a 26" flited #4 Hart 10 twist.
    It beats my factory 24" piped 300Wby hands down for velocity.
    * but again, to be fair, if my 300Wby had a longer pipe, (optimal length to take advantage of the case capacity) it'd win the race between the two, due to the larger case capacity of the Wby.

    It's an Apples to Oranges comparison.
    A hot rod WSM on a long action, is given all the advantages, vs a factory rifle in a standard magnum chambering, is basically handicapped in comparison.
    To be fair, you'd need to compare optimal to optimal barrel lengths, mag length, throats, etc. then it flip flops the discussion.

    If I had mine to do again, I'd still go with the long action WSM just cause I like it. Not to mention a 180 Accubond, over 3,100 fps with only 65.0 gr of RL-17 is just plain SEXY! (*Alliants recomended MAX of 66.0 gr of RL-17 was doable, but a ill too hot for decent brass life*)
  3. varmintH8R

    varmintH8R Well-Known Member

    Dec 12, 2011
    Winmag: makes perfect sense. Similar topic - how are you feeding yours? I had a smith tell me a WSM built on a LA will have issues feeding from an internal magazine, and he recommends going box mag. It came up in conversation and I was wondering what your experience is.
  4. winmag

    winmag Well-Known Member

    Dec 23, 2009
    My experience is very pleasant when it comes to feeding.
    The smith I had build mine is a compotent smith, & also a former sponsor of LRH.
    He knows how to build accurate rifles, & had great referances, but after some dealings we had, & the finished product I got back, I would not use him again.
    Too many shortcuts, & long overdue delivery, it was "shootable" kind of, but i had to have it finished by another smith after the season was over, because the flipping screw holding the rear tang stuck up so far that it interfered with the bolt cycling. That was how I recived it back. You know just "little stuff" like that, that sours a guy.
    There are some incredibly talented smiths here tho, & most all are quite reputable.
  5. tobbe

    tobbe Member

    Nov 6, 2013

    Hi Winmag.
    Good to read this .
    Iam having a 300wsm put together with almost the same specs as yours.
    Will be using a Schultz&Larsen Clasic DL long action with barrel change system ,
    Long actiion, Schultz&Larsen 26" barrels with 10 twist, these are cut barrels and then polished.
    1 300WSM barrel and 1 6,5x55 SE barrel.

    I would be very interested in load information for 208 gr A-max, 215 and 230 berger hybrids, COAL ? etc .

  6. minute of elk

    minute of elk Well-Known Member

    Mar 7, 2012
    Re: 300WSM questions

    I found a sweet spot (1/2") at 64.5 grains of R-17 in win brass w/br2's at 2.88" with 208's in my 300wsm tikka. I had every intention of running them longer, but they work well at mag length. I'm not 100% certain of mv, but the dope works pretty well with advertised bc & 2900 fps. (So it's probably faster)

    montanarifleman gave me some good advice, maybe he'll chime in
  7. MontanaRifleman

    MontanaRifleman Well-Known Member

    May 21, 2008
    Re: 300WSM questions

    I did shoot mine out of the SAKO short mag action. Did not spend a lot of time with the heavier bullets but pressure testing got me to 2930 fps with RL17 and 210 VLD's. The load IIRC, was 67 gr. The bullet was eated to just off the lands making it a single feed round. i did do some experimenting with mag length rounds and had to cut back the charge slightly and lost a little velocity, maybe 20 fps.

    This rifle did not shoot anything accurately so i can not comment on that. Only velocity potential. If i ever build another 300 WSM, it will be on a longer action and my primary bullets would probably be 215 Bergers which if seated to optimium case capacity would have a COAL of about 3.18