155 Scenar bullet ogive?

Discussion in 'Reloading' started by ronas, Aug 14, 2011.

  1. ronas

    ronas New Member

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    Aug 7, 2011
    Does anyone know the bullet ogive for the 155 Scenar? I wan tto compare it to the 155.5 Bergers I've been using.
     
  2. backwoods83

    backwoods83 Well-Known Member

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    Kevin Thomas would be the one to correct me if I'm a little off, but I'm thinking they are a 7 caliber short secant shaped more like a tangent than most vlds to maintain its bc at all velocities commenly used in the 308 where a lot of the flight will be under 2100fps, hope that helps.
     

  3. Kevin Thomas

    Kevin Thomas Well-Known Member

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    Hey guys,

    sorry for the delay here, but just got back from the Nationals at Camp Perry. Still trying to dig out from all the backlog of emails and all that good stuff.

    Can't say precisely what the ogive of our Scenar 155 is, as that's considered proprietary information. Most bullet makers take the same approach here, and are a bit shy about releasing such specs. However, I'd be more than happy to pass along open sources specs which are already published and on the market. According to Bryan Litz's measurments shown in his Applied Ballistics for Long Range Shooting, he cites the radius of the Lapua 155's ogive as measuring 3.289", with the Berger 155.5s at 2.954". The Lapua's is a secant ogive, whereas the Berger's Fullbore appears to be a tangent, so it's not a straight across the board comparison based on radius measurement alone. More to the point are his BC figures for each; .464 (G1) or .237 (G7) for the Berger vs. .462 and .236, respectively, for the Lapua. For all intents and purposes, their ballistic performance is identical.

    Hope that helps!