The MS Excel guru Hans Cronander presents models for R.L. McCoy / Gavre exterior ballistics. The source code includes an ODE engine based on a Bulirsch-Stoer variable step length numerical integration method for rational functions. Anyone devoted to VBA programming is welcome to further develop these calculators, as long as they share the improved code with the author (the 3DOF model needs to be complemented with more retardation functions). If the models or code from them are being used or sold commercially, the author claims either an OEM agreement or a $50 per copy sold royalty. The Cronander Excel models has been reviewed and accepted in the BrotherSoft Science listings and gets a rating 5 out of 5. The Review Staff give Cronander Excel models the maximum 5 out of 5 Rating because it is excellent compared to other programs in the section.