Sierra MK's Ballistic Coeffecient: The Truth Wanted

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Nodak7mm, Feb 23, 2002.

  1. Nodak7mm

    Nodak7mm Well-Known Member

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    Sierra MK\'s Ballistic Coeffecient: The Truth Wanted

    Gentlemen;

    Experiencing confusion! Gonna build a LR critter getter using high BC bullets. I want to use Sierra MK's in either 6.5 or 7mm. Now I have read several diferent documents that post the 7mm 168gr MK's BC @ .633 & .627 and I believe my Oehler Ballistic x-plorer gives a .633, yet at the Sierra website they give only .488 for that bullet. Is that a misprint? Anyone got the true answer to that? (I intend on calling the Sierra tech line on Monday, but can't wait)

    Gonna build either 6.5-06 Imp or a .280 Imp based on the higher BC. I am determined to use MK's as Primary bullet due to reputation, $$$ & availbility. I am aware of very high BC VLD's, but don't want to go there.

    Any help?

    Nodak7mm [​IMG] [​IMG] [​IMG]
     
  2. Dan Conzo

    Dan Conzo Well-Known Member

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    Dec 5, 2001
    Re: Sierra MK\'s Ballistic Coeffecient: The Truth Wanted

    Sierra had bad equipment when they first came out with the 7mm 168 MK and made an error in the B.C. They corrected it later on to .488. But the 168 MK does a great job at 1000 yds benchrest or deer. A overlooked bullet in 7mm is the 175 Sierra B.T. Spitzer, it has a B.C. of over .530 and is almost as accurate and kills good too, especially if you get it going about 3100 fps.
     

  3. Len Backus

    Len Backus Administrator Staff Member

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    Re: Sierra MK\'s Ballistic Coeffecient: The Truth Wanted

    I did some limited tests just before my Mexico Coues deer hunt last month with the 7mm, 168 grain MK. I think the .488 BC is about right.
     
  4. Tommy Vaughan

    Tommy Vaughan Member

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    Feb 9, 2002
    Re: Sierra MK\'s Ballistic Coeffecient: The Truth Wanted

    Is there any experience with the 150grain, 7mm Swift Scirocco yet, with an advertised BC of .53? Based on balistics tables, this BC combined with the increased muzzle velocity of the lighter bullet make it look very competitive with other heavier 7mm out to a 1000 yards and further. Is it accurate? or another X bullet?
     
  5. Varmint Hunter

    Varmint Hunter Well-Known Member

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    Dec 26, 2001
    Re: Sierra MK\'s Ballistic Coeffecient: The Truth Wanted

    I have experimented a bit with the 150 Scirrocco in an accurized 7STW. Although it does shoot well for a "premium" hunting bullet, it was regularely outshot by Nosler B-Tips and Hornady SST's. One could naturally assume that a quality "match" bullet would shoot better yet.