416-338 and 338 Lapua whats the difference?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by 300WSMMAD, Aug 7, 2008.

  1. 300WSMMAD

    300WSMMAD Well-Known Member

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    Hi Guys,
    Im a little confused, Ive been told that a 416-338 is differet to a 338 Lapua, but all I can find on the subject is that they are one in the same thing?

    In my quest for building a long reacher a friend of mine has been given a set of 3 reamers in a 416-338 IMP for me to have a look at to consider, will this be a improved 338 Lapua or a what they say a 416-338IMP?

    Sorry for the questions Ive been posting but rome wasnt built in a day!:D

    Bear with me,it will be built!

    Thanks guys

    300WSMMAD
     
  2. Varminator 911

    Varminator 911 Well-Known Member

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    Prefer Lapua

    You could build a 338 off the 416 Rigby or the 416 weatherby. They are similiar cases but the Rigby doesn't have a belt. The 338 Lapua is a much different case, way stronger and much better brass. Most people think the 338 Lapua or 338 Lapua AI are better than building around either 416. The Lapua would be my choice.
     

  3. 300WSMMAD

    300WSMMAD Well-Known Member

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    Yes with the info I have just got, I agree!
    Im sure I can Hi jack my on post so,
    in regards to velocities in a 338 Lapua what sort of FPS would I expect out of a 30' barrel?
     
  4. Roll-Yur-Own

    Roll-Yur-Own Well-Known Member

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    300 smk about 2650-2700. Improved may go faster but not worth it IMO.

    It is an accurate long range round but not a high velocity round.
     
  5. 300WSMMAD

    300WSMMAD Well-Known Member

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    Roll yur own,
    UM, I dont know its a retorical question, but, the research Ive done would indicate that out of a 30" barrel I would expect 3000 fps, the numbers youve said dont kinda add up to me thats all, 2750 fps is what I would expect out of a 24"-26" tube not a 30".
    From ADIs web site 94.0 Grs AR2225 out of a 24" barrel gives you 2654 fps, rule of thumb 50 fps per inch, so with a 30" barrel 50fps x7 = 350fps faster, even a 28" will give you 200 fps faster.

    Is 3000+ fps possible out of a 338 Lapua or do the numbers lie?

    Thanks 300WSMMAD
     
  6. AJ Peacock

    AJ Peacock Well-Known Member

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  7. Fiftydriver

    Fiftydriver <strong>Official LRH Sponsor</strong>

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    The Rigby case has an overall length of roughly 2.900" and has little body taper. The Lapua has alot of body taper and is only 2.700" in length case wise.

    So the Rigby has much more case capacity so it will produce more velocity right?????

    Not really, its a weak case design, not really intended for use over 50,000 psi in its traditional load levels. Although the Lapua has a smaller case capacity its designed to handle much higher chamber pressures. In fact I have seen some tests were loads were using 70,000 psi loads and handling things fine.

    The 338-416 Ricby will get you around 100 fps more then the Lapua because of its huge powder capacity. But if you use the improved version of the Lapua, it will also get you 100-150 fps more velocity as well and do so with less powder then the Rigby and no brass forming needed other then fireforming which is also needed with th e338-416.

    The 338-378 Wby really made the 338-416 Rigby obsolete as they are basically the same thing but the Wby has the belted case design.

    Again, in this class of chamberings, you will see 15 to 18 fps per inch of barrel length for velocity increase.
     
  8. Roll-Yur-Own

    Roll-Yur-Own Well-Known Member

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    Exactly, Longtimelongranger told me that year ago when I bought my lapua. I load my Lapua to get about 2700 and I have a 28" barrel.

    The problem with the improved is that the hassle of fireforming the cases is not worth the added velocity gain. The Lapua is a very accurate cartridge but it not a super fast one. Velocity only gets you so far. If you want more then go with one the 338 edge. it is a 300 RUM necked up to 338. (FYI: the 338 RUM uses a smaller case that is why the egde uses the 300 RUM case which has more capacity) I believe he is getting a good 2900 from a smk. I can't recall exactly. The only thing required is a set of dies from redding. It pretty easy to neck up 300 to 338. And, you don't have to fireform. The only downside is that you don't get to use lapua brass but I believe Nosler Custom Brass makes 300 rum brass.

    If you really want Hard hitting AND high velocity go with one of Kirby's Allen Magnums.
     
  9. Lightvarmint

    Lightvarmint Guest

    Hello,

    Just for reference, down here at sea level, I get 3000 fps out of the Hall Express 338 Lapua Improved using the 300 SMK. I get many case reloadings at this pressure level, velocity spread is minimal (ie <10) and accuracy is very good. However, I have since switched to a 265gr aluminum tipped bullet with the same BC as the Sierra but it will fly 200 fps faster than the 300 SMK. I also get the same results (within 15 fps) out of an equivalent length Hall Express 338/378 using the same bullets.

    James
     
  10. Magnumdude

    Magnumdude Well-Known Member

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    Kirby,

    Do I have to have a rifle assembled in your shop to shoot one of your cartridges? Or can I buy a reamer for the .338 Allen Magnum and the brass and have my gunsmith build a rifle around your .338 Allen Magnum?

    Thanks,

    Ralph Jones