.338 250 grain MK's?????

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by goodgrouper, Mar 30, 2006.

  1. goodgrouper

    goodgrouper Well-Known Member

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    .338 250 grain MK\'s?????

    Ok, someone is fibbing here. Sierra says their 250 grain MK has a bc of .587. Lapua says their 250 grain Scenar has a bc of .675. Well, I put the two close together today and looked at them and there is no way there could be that big of a difference in bc because the two look almost identical!! Bearing surface, boat tail, ogive, and tip are almost exactly the same. So who is fibbing?

    ANyone done a bc test on the MK? I am betting it has a higher bc than what they say and by a long ways. Either that or the Scenar is way lower than what is rated. Everytime I dialed in the Scenar for 1k off the ol' computer, it landed low by a minute and a half so I'm inclined to think that it isn't .675. I would bet they are probably both closer to .625.

    Anyone know for sure? I know there are lots of guys shooting the 250 MK.

    If the MK is really that low, it would do no good to shoot it over the 225 accubond.

    Any help would be greatly appreciated.
     
  2. Ballistic64

    Ballistic64 Well-Known Member

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    Re: .338 250 grain MK\'s?????

    How about the 300 gr MK at .768? /ubbthreads/images/graemlins/grin.gif
     

  3. royinidaho

    royinidaho Writers Guild

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    Re: .338 250 grain MK\'s?????

    GG,



    I'm thinking that you are a bit out front of most of those/us using the 338 cal. Your experience, as stated may well be "state of the art" info. Maybe I'll do some comparison testing when I get the 338 RUM shooting. It won't make much difference if that bbl is abused a bit. If it were me I wouldn't want to put that kind of wear on the Thunder bbl. /ubbthreads/images/graemlins/crazy.gif


    <u>D C</u> says "If you check the BC of the 300 Gr MK you will find it is right at .787 as per actual fire." (on the longest shot thread.....)
    Doesn't the .787 for the 300 kind of rhymn with your .625 for the 250.

    With the 250gr at 3150 would the 225 accubond hang with it, out there a ways?
     
  4. goodgrouper

    goodgrouper Well-Known Member

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    Re: .338 250 grain MK\'s?????

    Got a gun that shoots those already. And with a significant increase in recoil going from the 225's to the 250's, I don't think I would want to shoot the 300's out of this gun prone. It only weighs 9.5 pounds!
     
  5. goodgrouper

    goodgrouper Well-Known Member

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    Re: .338 250 grain MK\'s?????

    Well thanks for the kind words my friend, but my experiences aren't really "state of the art" as much as they may seem. As far as the 338 goes, I've only got concrete data on the 300 grain MK's and the 225 Accubonds. These Scenars are new to me entirely and they have a whole set of new rules apparently. I'm learning as I go.


    When I was testing bc on the 300 grain MK's at 11,000 feet, the bc proved itself time and time again at .820. I think the 250 MK is probably much higher than what they are saying and DC seems to have good evidence that they are in fact higher too.


    [ QUOTE ]
    With the 250gr at 3150 would the 225 accubond hang with it, out there a ways?




    [/ QUOTE ]

    Well, that is what I'm trying to figure out. If the 250 MK really is .587 and the 225 ab is .550, there would be no reason on earth to shoot the MK. The accubond would smoke it in drop, equal it in drift, surpass it in velocity, and be only a few ft-lbs less energy. All while giving more consistent close/long range dependability maybe?

    Now if the Scenar is truly .675, it would smoke the ab and the MK in every category clear out to 1760 yards! The only thing it would not be as good at against the 225 ab is velocity at 1000 yards but that is of no matter.

    The Scenars ballistic capability is what prompted me to design the whole cartridge around it. I'm crossing my fingers that it works on game. MOre testing is in order.