Lapua BC changed for 338 Lapua Magnum?

[Arif]

Quick question about BC for Lapua Ammo. All my ballestics calculators tell me that the BC for 338 Lapua Magnum 250 grain Scenars is .675 but today i was on the Lapua site and it is sying that the same bullet has a BC of .645. I am not sure the diffence, appreciate your comments as i am sure this will impact the ballestic calculator output


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[elephantrider]

Re: Lapua BC changed for 338 Lapua Magnum?

I noticed that Lapua has changed/updated their G1 ballistic coefficients. The older 2010 datasheet that I have listed higher G1 BCs across the board. They have also added G7 BCs in addition to the G1 BCs. Your calculator has the old G1 BC listed in it's library. If you can directly enter your own bullet parameters into your calculator go ahead and directly enter the newer BC from Lapua. Better yet directly enter the G7 BC listed by Lapua, as it will likely be more accurate at long range.

 

[MALLARD]

Re: Lapua BC changed for 338 Lapua Magnum?

probably because the dimensions of the bullet have changed. Yes it will affect your ballistics, but not much unless your shooting 1000y and beyond.

 

[Arif]

Re: Lapua BC changed for 338 Lapua Magnum?

thank you, i have changed the data in my calcualtors directly. I am aslo going to provide feedback to tHE program Developers of Ballestics FTE and ISnipe to update their software, thanks


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