.338 lapua improved 40degree

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by 300spanker, Mar 15, 2010.

  1. 300spanker

    300spanker Well-Known Member

    Messages:
    51
    Joined:
    Aug 2, 2008
    I have decided to have a .338 lapua improved put together. I was wondering if i have a 29 inch barrel, how much velocity would i see with the 300gn. smk
    thanks,gun)
     
  2. c_bass16

    c_bass16 Well-Known Member

    Messages:
    457
    Joined:
    Sep 22, 2009
    What powder and amount are you thinking about running?
     

  3. 300spanker

    300spanker Well-Known Member

    Messages:
    51
    Joined:
    Aug 2, 2008
    a friend of mine said 100to102 grains of retumbo maybe a little more??
     
  4. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

    Messages:
    2,612
    Joined:
    Mar 12, 2002
    I thought I answered this for you on another thread. You are going to top out with best accuracy between 2850 and 2950 fps. Just depends on your barrel. In other words you should be able to get near 2950 fps out of it but your best accuracy may be under 2900 fps.
     
  5. 300spanker

    300spanker Well-Known Member

    Messages:
    51
    Joined:
    Aug 2, 2008
    would i do any better with a 338-378 improved, i am looking for 3200fps without going to snipetac or allen mag. thanks for ur patience i am new to this long range world, gun)
     
  6. Autorotate

    Autorotate Well-Known Member

    Messages:
    503
    Joined:
    Apr 2, 2007
    You won't get those velocities using the 338 Excalibur/338-416 Rigby Imp/338-378 Wby Imp/338 Kahn, unless you use extremely long 38"+ barrels, and don't want to shoot your cases more than a few times:)

    Here's a good post Kirby made regarding 338 velocities.
    http://www.longrangehunting.com/for...ber-build-advice-33343/index9.html#post252002

    LTLR has owned them all...he'd be a good reference to query.

    Let me suggest the following, since you stated you were "new" to the long range world....In order to obtain the best feedback possible from the forum on your rifle build, start a new thread called "Help me with my new long range build".

    Define your build goals in the post by using the following points:

    1. Your shooting experience?
    2. Current reloading experience?
    3. Budget?
    4. Intended target-Paper/steel or fur or both. If fur list the critters (moose, bear, elk, caribou, deer, sheep, varmints, etc)?
    5. Intended distance for the above target?
    6. Desired weight (backpacker, horse, atv or truck hunter)?
    7. Acceptable barrel life in # rounds before you should expect to re-barrel?
    8. Prefer a SAAMI cartridge with off the shelf dies or a Wildcat with custom dies?
    9. Do you prefer a Repeater or Single Shot?
    10. Do you prefer a custom action or do you have a factory action you want to build from?

    There are so many different ways to skin the proverbial cat, that without defining the above, the counsel/advice you receive may be piecemeal and incomplete...by outlining the above, your answers will be focused on your goals and preferences.

    Please don't take my post incorrectly....the folks on LRH want you here on the forum, before, during and after your rifle build. But by doing the above you'll allow one central point for all the wisdom that's on the forum to contribute to your build. This forum isn't like others, that the senior smart folks don't have time for questions....great group here.

    Good luck, and look forward to hearing about your build and be sure you post up with pics when it's done, and when you harvest something with it!
     
  7. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

    Messages:
    2,612
    Joined:
    Mar 12, 2002
    Good post, your right 3200 fps is not possible without going to the chey-tac case. In a standard hunting weight rifle you could hit 3100 fps with a fast 30" barrel in something off the 378 case or 416 imp case. I have done it but that doesn't mean that is where your accuracy is going to be. The ones off the 378 case and the 416 rigby imp are the fastest ones out there unless you go to the chey-tac case. I have built about everything out there since the 70's trying to come up with the fastest in a hunting weight carry rifle. I have seven 338-378 wby's in various styles right now along with several other big 338's. Three of the seven get good accuracy loads in the 3050 fps range. That is about the best you can hope for. I had a 1000 yard range in the back yard behind my old shop and shot many rifles head to head. That majic bullet just ain't there. Accuracy is the key.
     
  8. uncleB

    uncleB Well-Known Member

    Messages:
    558
    Joined:
    Aug 19, 2005
    I agree with most of what LTLRanger has said, it is not possible to get 3200fps with this round.
    I have been shooting the 338 Lapua AI since 2004-2005 and with a 36" barrel it was shooting the 300gr SMK at 3050fps, the barrel was cut back to 33" and it now clock's 2975fps.
    RL25 has been the powder of choice.
    UB
     
  9. BountyHunter

    BountyHunter Writers Guild

    Messages:
    4,790
    Joined:
    Jun 13, 2007
  10. 300spanker

    300spanker Well-Known Member

    Messages:
    51
    Joined:
    Aug 2, 2008
    Thanks for the reply from Long time long Ranger. do u have any input about the snipetac or the allen magnum versions. thanksgun)
     
  11. jwp475

    jwp475 Well-Known Member

    Messages:
    2,595
    Joined:
    Feb 4, 2005
  12. tom m.

    tom m. Well-Known Member

    Messages:
    82
    Joined:
    Jan 17, 2009
    3,000 fps if it's a very fast barrel, but count on about 2,950. that answers your origional question, now some opinion:D

    i can tell you, for a fact, 2,982fps with the 300smk, at 3,200 feet, will land predictably at over 2k..... why did you want or need it to do 3,200 fps? i can also tell you, that combo will break a deer at 1,589 yards...

    numbers are cool, but accuracy kills, or wins, dependeing on the sport. i once, when i was new:rolleyes:, thought speed was everything too. i managed to get into the 700 yard club back then, with a long tubed 30-378. and then lightbulb, it hit me, i have to crank these knobs on every shot past 400 yards anyway, hmmmmm....

    do as you wish, but i think you would be quite happy with a 338 lap imp., the brass is top notch and lasts forever(ish).

    good luck with whatever you pick,
    tom
     
  13. jessej

    jessej Member

    Messages:
    10
    Joined:
    Apr 14, 2010
    Im new, but im sending 300grn smks outa my 338 RUM at 3000 fps using 100 grains of retumbo. I would hope that you would be capable of more.
     
  14. 300spanker

    300spanker Well-Known Member

    Messages:
    51
    Joined:
    Aug 2, 2008
    how long is your barrel. most guys can only get 2800fps out of a 338 ultra.