What cartridge on Raptor receiver?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by bigngreen, Oct 12, 2011.

  1. bigngreen

    bigngreen Well-Known Member

    Messages:
    6,208
    Joined:
    Nov 24, 2008
    I'm not even done with this years season and I'm already looking to next years projects, I want to build my first full on custom high performance rifle but I don't quite know what to chamber it in.
    I'm set on building on the Raptor receiver, Brux barrel with a 4-port Muscle Brake, Manners stock with Seekin bottom metal.
    Caliber in 338 or 375 though I kinda lean towards the 338, I've been a minimalist in the past but after shooting a 338 RUM I put together for my buddy I can hardly put it down, absolute pleasure to shoot but I want to take it up a notch from that level.
    I was thinking something like the 338 Lapua Improved or something along those lines, is there a 375 Lapua Improved, Excaliber? What's out there that would fill this receiver?
     
  2. Outlaw6.0

    Outlaw6.0 Well-Known Member

    Messages:
    3,097
    Joined:
    Feb 18, 2010
    Interesting coincidence, I was just thinking about a 338 Lapua Improved this morning. Even more so interesting, I have a custom 338RUM I like beating on...:D

    The idea of a 375 improved is intriguing, although to my extremely limited knowledge the 350 SMK is in short supply... are there any other worthy projectiles?

    This should be an interesting thread!
     
  3. bigngreen

    bigngreen Well-Known Member

    Messages:
    6,208
    Joined:
    Nov 24, 2008
    Bullets would be Berger 300gr OTM in the 338 or Cutting Edge bullets in a 375. I just don't really know what is out there between the RUM level and the Cheytac.
     
  4. Broz

    Broz Well-Known Member

    Messages:
    8,638
    Joined:
    Feb 3, 2007
    BnG, the more I shoot my .338 LM the more I like it. The introduction of the new Berger 300 gr Hubrid OTM's sure have not hurt any either. At over 1300 rounds now, you know I dont worry much about the bore rusting.:D The AI might be worth the extra effort of fire forming and getting a set of well fitted dies. I am still on the fence on that. Don't think either is a bad choice. Brass quality is impecable and lasts a long time. Past 13 firings anyway. Glad you are thinking .338 or bigger, the .338 is easy to get love affair going with for sure.

    Keep us posted

    Jeff
     
  5. jmden

    jmden Well-Known Member

    Messages:
    2,740
    Joined:
    Nov 2, 2003
  6. angus-5024

    angus-5024 Well-Known Member

    Messages:
    1,141
    Joined:
    Jan 22, 2008
    I would go with .338 Allen Xpress. I think its the biggest, badest out there that can be formed with Lapua brass. I would talk to Kirby and see if he's far enough along with his R&D with this new faster wildcat before making up my mind. Sounds like a fun build though!
     
  7. bigngreen

    bigngreen Well-Known Member

    Messages:
    6,208
    Joined:
    Nov 24, 2008
    Jeff, I really didn't like 338's till doing some shooting of yours then after building this one for my buddy which I've shoot way more than he has :D If a guy builds them right they are about the sweetest shooting rifle I've been behind but when they land on the target the 338's are as impressive as they are sweet to shoot specially with these Bergers. So I'm blaming this on you, don't worry my wife can't shoot to far gun)

    I need to stay with non-proprietary chambering since I would be doing the work myself. The straight 338 Lapua would be an option but in this awesome of an action I would be leaving a lot of performance on the table, the thought of a 375 Lapua Improved is really interesting but I've not been able to find any hint of what kind of performance one could get or the feasibility of it. The Lapua brass would be a big plus for something on the 338 Lapua!!!
     
  8. jmden

    jmden Well-Known Member

    Messages:
    2,740
    Joined:
    Nov 2, 2003
    Oh...doing the work yourself... There's plenty of 338 Lap Imps out there.

    Might check with the various reamer companies to see what they have. Not sure about 375-338 Lap Imps. I did see a post awhile back saying that Kirby had a 375 Allen Xpress, but I can't say for sure. Certainly worth investigating.

    Just design your own! Talk to Pacific Tool and Guage and they'll set you up and guide you right through the process. I did this with a reamer I had made some years ago.
     
  9. SHRTSHTR

    SHRTSHTR Well-Known Member

    Messages:
    565
    Joined:
    Aug 29, 2008
    Good advise by all!

    I have and like my 338 Lapua Improved. I am pushing 300gn smk's at 2955fps. This is my accuracy load. Bergers are a little faster, 2985fps got my lowest ES.

    As Broz indicated, fireforming and custom dies seem to be the biggest issue. I purchased blank sleeves from Redding and used my reamer to modify dies for the Imp. I also bought Neil Jones dies. Be prepared to wait 3-4 months for NJ dies (I had to anyway).

    Fireforming is kinda of a pain. I did barrel break in and load development during the fireforming process. Having said that, I really like the fact that I only need 17.2 moa up at a 1000 yards with the Bergers and 18.0 moa up with the smk's. I have a 300 yard zero.
     
  10. MT4XFore

    MT4XFore Well-Known Member

    Messages:
    708
    Joined:
    Oct 20, 2005
    If you haven't been there already, go to Home Page. I think that the answers to all your questions will be there. Be prepared to stay awhile, lots of good reading and gun porn!
     
  11. pitbull320

    pitbull320 Well-Known Member

    Messages:
    154
    Joined:
    Feb 28, 2008
    just another to think about would be Kirby's 338 ultra max I got mine this year and I'm very impressed with it I'm getting 3090 out of a 30" barrel and 300gr Berger
     
  12. bigngreen

    bigngreen Well-Known Member

    Messages:
    6,208
    Joined:
    Nov 24, 2008
    Kirby's web site should have some real sleazy music playing in the back ground while you surf it :D I missed the cartridges the last time I check for them, the Raptor page has been thoroughly violated :D

    I really have a desire to go the 375 route but looking at the reality of the performance in the Lapua size case the 338 would be a better fit. By the looks of it a guy really needs the Cheytac case to really take advantage of the 375, I think trying to do a 375 would be getting the cart in front of the horse at this point and I need to calm down!

    Grabbing another 200fps with the 338 does really show some gains with a bullet like the Berger, some version of the Lapua improved seems to be the clear winner and the brass quality should make it a no brainer I guess. What version though, I've heard there is a bunch of them but I need something I can buy a reamer for from PT&G. Waiting for dies won't be bad, at the rate I finish things not a worry!

    The purpose for the rifle is to build my first full on custom myself and to step up the performance level above the 338 RUM and to WHACK elk! A lot of hunting areas deer are the main deal with a possibility of elk, for me it elk, elk and more elk!
     
    Last edited: Oct 13, 2011
  13. Good

    Good Well-Known Member

    Messages:
    412
    Joined:
    Jul 15, 2009
    Sir, the 338-408 Chey Tac is hard to pass up. I'd look real heavy into the 375-408 if it were me and my money. If I were going to build a gun like this, I'd make sure it was legal anywhere I wanted to hunt- Africa, etc. Personally, I only want to do that once as I'm not much of a tinkerer and have other things to spend my cash on, but I like to shoot, early and often:D.

    Build a gun and shoot it. Once there's a gun for all species and events (some calibers could be crossovers), just spend time shooting them all, focusing on specific ones especially if you have a specific hunt coming up. For my current income and level of available time, I'm just trying to save to get a 338RUM takeoff barrel screwed on my Rem 700 action. That's going to be my first .338, but if I were to build something, it would likely be a 375-408 or something really similar. Like Nike, just do it.
     
  14. phorwath

    phorwath Well-Known Member

    Messages:
    6,075
    Joined:
    Apr 4, 2005
    Good Thread. My only hesitation in subscribing is this could get way infectious. I'm already feel some form of .338 Plague.