Load Base3 PC and PDA -UKV Special Offer

Deserttech Europe · May 19, 2011

We are please to announce a temporarily reduced price on Patagonia's Load Base Ballistic solution for members of UK Varminting.

Till end of May we are offering Load Base software for the discounted price of £80.

In addition to this special price a £5 donation from each sale will be made to Help For Heroes.

This gives you the chance to get hold of this amazing software at a good price and do something good at the same time.

Below is a little on the software written by the programmer, this is amazing stuff that allows comparison of loads/ rifles etc as well as having an extensive library, conversion functions, and a log book.

What is also neat is the synch function to a windows PDA allowing you to take all the same data into the field with you.

Full detail is here: http://www.patagoniaballistics.com/feat_int.html

By taking advantage of this deal, you will save money but have absolutely exactly all the same functionality and direct access described on the patagonia website.

As an example of its accuracy we recently stretched its limits and a shooter managed 30% hits at 1280m from a 22" .308 shooting 168SMK....I was gobsmacked. The elevation was spot on and the misses were either side due to wind.

If seriously interested post here!!!

The ballistics engine of LoadBase Desktop & Mobile editions© while based on the work of Professor Arthur J. Pejsa ( who finished his research circa 1953 ) includes numerous proprietary extensions, making it a highly developed derivation of Pejsa's original method. Meaning it has no velocity or range restrictions, covering the full spectrum from supersonic, transonic and subsonic trajectories at extended ranges with muzzle velocities starting at any sonic boundary, giving a continuous, non-linear solution.

Many enhancements to the algorithms were developed, using both iterative and recursion approaches to solve the problem of computing downrange figures for velocity, time of flight and drop, the main variables of the solution from which others parameters are derived.

The model is an analytic, closed-form solution that doesn’t use tables generated for standard-shaped projectiles, a fact of paramount importance, since while it does not rely on the G1/G7 drag model used in most of the available programs, (some following the Mayeveski-Ingalls tables), the present method can use a readily available, G1/G7 ballistic coefficient as published, incorporating a custom drag function in order to model the specific projectile.

Since it effectively uses an analytic function ( of Mach number ) in order to match the drag curve of the specific bullet, it does not need to rely on other drag tables to approximate a better fit.

A ballistics software foundation rests in its ability to predict accurate trajectories, matching field results as the ultimate test.

Nearly all ballistic software take for granted that a specific drag function correctly describes the drag characteristics of a bullet as related to its ballistics coefficient, consequently, whether the bullet style is a flat-based, spitzer, a boat-tail, ULD, etc they take care of them to the same drag function as indicated by the published BC, usually the G1/G7 function.

The state of the art mathematical approach taken here, is quite different and a major improvement, of special application to the long range shooter.

Being practical, the use of the published BCs data as available, by almost every major bullet manufacturer is almost mandatory. However this program does not use it to calculate the changes to the drag function over the supersonic velocity range. In other words, this program ballistics engine uses a drag coefficient (DC) that affects the calculated rate of bullet deceleration.

Applying this DC, the resultant trajectory calculations are very accurate for that particular bullet because the drag function has effectively been tailored for that particular bullet.

As the drag coefficient can be modeled as a simple function of the Mach number, the particular functional form of the drag coefficient allows variations in the shape of the drag curve to be considered parametrically.

It's easily demonstrated that the projectile trajectory and velocity history can be characterized in terms of three parameters: the projectile’s muzzle velocity, a parameter related to the muzzle retardation, and a single parameter defining the shape of the drag curve.

Other approaches ( on the market ) base their predictions on trying to make a match of a specific bullet ( yours ) to like drag data which is available to examine the variation of the drag coefficient with Mach number in the standard axisymmetric ( having symmetry around an axis ) projectile shapes, that were tested in the early to mid-1900’s.

These resulting drag curves are referred to as the Ingalls, G1, G2, G5, G6, G7, and G8 drag curves.

Most bullet manufacturers assume and publish the G1 drag function shape. Examination of the form of a G1 standard-projectile, will to the obvious conclusion that it doesn't apply to the modern boattail bullet shapes in common use today. The G7 or G8 shape is much more appropriate but general availability of these ballistic coefficients is almost nonexistent.

Particularly, the G1, G5, and G7 curves model a specific bullet form, since they were deduced from, and it's common for some programs to adapt ( modify ) the G1 drag curve in an effort to fit the G5 to G7 bullet shapes, and in other words, these approaches are, at best an improvement to model modern bullet shapes in order to make predictions more accurate.

That's why the BC must be defined as a function of velocity. The present solution uses the actual drag, and not rely on an average fit to a non-representative standard or table-based drag function.

In short, what these models can, is to compute accurate trajectory values if range is moderate, up to approximately 600 yards, beyond that, you need a different way to model air drag and to account specifically for a drag curve that matches your bullet dynamics. This is what this method does precisely.

The method used here takes on a different approach, since if the shooter takes the necessary effort to actually measure the Drag Coefficient, the model will make an almost perfect fit, under different environmental conditions, thus yielding very precise downrage values for Velocity, Time of Flight and Drop.