OzFclass

Every once in a while you strike gold while searching for something on the World Wide Web. I was looking to turn a table that Bryan Litz had used to compare calibers and projectiles into a spreadsheet. Not being a ballistician or a physicist I started searching for a set of formulas I could use. What I found was something else altogether, a complete set of ballistic functions written for Excel.

I discovered a Dutch physicist named Robert Meijer who is a long range shooter and has a website called BfX Online, http://www.bfxyz.nl/ that answered all my questions. He has a complete set of ballistic functions he calls BfX() that can be downloaded and installed into Excel as an add-on.

To cut a long story short I had no trouble at all putting together a spreadsheet that did exactly what I wanted. Read the article about using BfX functions to achieve what I wanted here, http://www.safclass.com.au/CompareCalibres.html

If you have a need to do some calculation or comparison that involves ballistics then take a look at Robert Meijer's incredible website.

IanP

ian,
you can now compare the 180 berger with the new 180 sierra!
you might have to include price and accuracy to get any difference.
bruce moulds.

Yeah, I saw that on 6mmbr.com the new Sierra 180 grainer has a close enough to identical BC as the Berger 180gr VLD. No need to run it thru the math functions, just check the price and buy whatever is best value.

The BfX functions includes drag model (G1-G8, GS, GL, RA4, GC and A) so it has your black powder projectiles covered. Even gives example of using some of the functions to calculate BC, just what you have been looking for!

IanP

yeah i read that about the 180 sierra aswell but they reccomend a 1-8 twist??

the 180 berger only needs a 1-9 so i cant see why the sierra needs a 1-8?

OK, going by this chart I will be building a 7mm RUM full of Vihta Vouri N570 and shoot 200gn Wildcats. This will bring me fame, fortune and adulation by the masses. Ooops, just checked the recoil , 22 J for the 7mm RUM VS 4J for my Dasher and 11 for my 284. Back to what I have for now.

Good program though Isnt it.

Adam,

If you drink the RUM, then you will be NUMb, and you won't have to worry about the recoil.

Bartman

I have had a go at setting out a method of approaching long range target shooting in a 3 part series of articles mostly aimed at new comers. Look here: http://www.safclass.com.au/BallisticBasics.html

IanP