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General discussion / The strategy of a Match ....
January 15, 2011, 10:40:43 PM
I found on the website of the South Australian F-Class the following (part of) an interview with Brian Litz The reasoning might be explored with the WhatDoIShootToday spreadsheet I released lately...

You're eluding to the development of higher BC .30 caliber bullets which are currently under development (no timeline yet on release dates).  The new .30 caliber bullets will have much higher BC's than any existing line of bullets.  Since they're basically scaled up copies of the new 7mm Hybrid, the BC's on the new .30 cal Hybrids will be higher than the 7mm's.  Will they be favored over the 7mm's?  That's a question I think will be governed by each individuals thoughts/feelings about recoil.  Consider the 6.5mm vs 7mm debate.  The consensus seems to be that the 6.5mm is inherently more precise than the 7mm's, probably due to the effects of recoil on the platform and shooter.  However the 7mm is a better ballistic performer, so there's a trade-off.  The introduction of high BC .30 caliber bullets is simply an extension of that same trade off.  Rifles built to shoot the new .30 caliber heavies (~230 grain range) will probably be capable of less inherent precision than the 6.5mm's and 7mm's, but will be even better ballistic performers than the 7mm's.
For those seeking advice regarding the trade-off between precision and ballistics, I'll offer the following.  Consider the scores and standings during a long tournament or season aggregate.  On the relays/days/matches where the conditions are good (this is where the smaller, more precise calibers do well) the point spread in the standings is very small.  In other words, the top twenty places are only separated by a couple points.  For example, the 200's, 199's, and 198's might be fired with the 6mm's and 6.5mm's because they tend to be more precise, and the 197's, 196's, and 195's are shot by the 7mm's and .30 cals.  Now if the event is long enough, there is going to be at least one, likely several relays/days/matches where the conditions are horrible.  On those inevitable days, the point spread is greater, and the larger calibers have the advantage.  Now the larger calibers (better ballistics) are shooting 195's, 193's, and 191's, while the smaller calibers are getting all blown around in the wind and shooting in the 180's.  Here's the important conclusion to draw from the above analysis: It's better to optimize your equipment for the situations when the point spreads are large.  Imagine you're shooting a 7mm in a 3-day tournament.  It's calm the first two days and you're a couple points and a bunch of X's behind the smaller calibers.  Now the last day comes, and with it, the inevitable wind.  You can make up more on a windy day with superior ballistics than you're likely to lose in two days to slightly compromised precision.
Of course things don't always play out as described above.  There are exceptionally precise large caliber rifles, and exceptionally talented wind readers shooting small caliber rifles.  However as an analysis of general trends, I've participated in the scenario above many times.
Updates / New releases!
January 14, 2011, 02:45:54 PM
I released new versions of BfX and some workbooks. BfX is extended with bfx_u() that allows for easy conversion of units. Furthermore the interpolation function bfx_i() is improved. See getting started. Both functions are also available in VBA.

One of the workbooks I created is an multi distance multi target simulator of shooting matches taking into account varying wind conditions as well as the ability of the shooter and his equipement. To do so the workbook contains a lot of code. Take care to set the proper path to bfx(64).xll! in many modules!
General discussion / Re: Newbie intro
January 10, 2011, 04:35:51 PM
thanks, what are the problems?

... it will be a real challenge to built a rifle that can launch a 90 grain .223 bullet. But when it flies stable the ballistics is unbeatable - for a paper punching F-Class purpose.
the brewing is done, creating the possibility to test it with 32bit office 2007 is delaying the release. Tests with  Excel 2003 and Excel 2010 (64bit) have been completed ...
I have developed a nice simulator in which the effects of cross wind and shooter accuracy on a match (i.e. a NRA 6 distance full prone course, or the Dutch 300,400,500m match) is calculated. Under Excel 2010 it runs nicely, however the VBA code has a few bugs under Excel 2003 which I have to fix and for which I have no time. Have a preview at its graphical output.
General discussion / Re: Two more functions coming
July 09, 2010, 10:33:15 AM
and in case you are wondering for which one could use such functions: they allow to simulate a shooter...
General discussion / Two more functions coming
July 01, 2010, 12:49:29 AM
in a few weeks I will release a minor upgrade: bfx_u will be added: =bfx_u(output_unit;value;input_unit) for unit conversion and =bfx_rang(iseed,center, standarddeviation, low,high) that generates a random number between low and high according to the normal or gaussian distribution centered at center with standarddeviation as width).

Furthermore a new workbook will be released that simulates a complex, multitarget shooting match
Most likely you need to use the automatic installer to supply your computer with additional files that BfX depends on. I use the latest Visual Studio compiler that came out at the end of May 2010. chances are huge that your PC does not have software that is produced with this - hence BfX is the first one, and you have to install additional Visual Studio files that BfX uses (use the automatic installer of BfX)
Quote from: david on May 31, 2010, 08:37:39 PM
Quote from: admin on May 15, 2010, 11:43:11 PM
Dear Downloaders,

downloaded software and workbooks I think OK, but struggling to get an understanding of this material despite being mathemtical type and spread sheet user.
sure I will crack it soon.

David, what do you want to do?
oops, due to wrong links on the download page the iron sight calculations were popular .... ;D
please report experiences
The 64bit Excel2010 is fully supported
.... however, it has to be tested. Furthermore, the visual basic definitions have to be adapted.
Dear Downloaders,

give me some feedback. Does the installation work? Why is the iron sight settings downloadable so popular?