Internal Ballistics Home Page
by Fabrique Scientific, Inc.
This page presents a summary of internal ballistics theory and offers some programs and peak pressure measuring device.
Warning: the theoretical formulas and programs presented below cannot be used to calculate loads for small arms, due to their high sensitivity to initial conditions such as the bullet pull force, chamber throat length variations, bullet engraving forces, and powder grain burn rate deterrent coatings, without verification from empirical measurements such as those presented in reloading manuals. Large guns/cannons do not suffer from the same caveats and are easier to model.
Internal Ballistic Modeling Software:
- Le Duc Model Le Duc program for DOS.
- Coppock's Model now shareware with more functionality (DOS)
- NABM for Windows with graphing capabilities. Improved for use with any screen size.
- NABM without the BDE Use this if you already have the Borland Database Engine installed.
- Strain 3.0fWindows 95 Program for computing pressures from strain and gun chamber dimensions. This version adds statistical calculations for results, and plots pressure curves using the Heydenreich Model - given a measured peak pressure and muzzle velocity. Now with LeDuc Model and graph printing capability. Also with Strain to Pressure conversion graph (printable). Now works with piezo. efficiency of .1 to .55.
- Strain 3.0x version information
Chamber Pressure Instrumentation:
Featured in Aug '97 Handloader Magazine!
Handloader #188, "Powder Temperature Sensitivity and the AR15", Steve Faber
Tactical Shooter - July '98, ".408 Cheyenne Tactical (TM)- A Novel 2,000 Meter Tactical Cartridge", John Taylor
Wildfowl - Aug/Sept '98, L.P.Brezny - Shotgun load measurements
Wildfowl - Oct/Nov '98, L.P.Brezny - Review of system
Tactical Shooter - Jan '99, "The .338 Lapua Magnum Cartridge: Origin, Development, and Future", John Taylor
Gun Digest 2000 - Reloading Column - Larry Sterett
Tactical Shooter - May 2000, ".408 Cheyenne Tactical(TM) - A Novel 2000 Meter Tactical Cartridge part 2"
American Rifleman - July 2000 - Reloading Column - L.P.Brezny
Tactical Shooter - Oct 2000, "MAG-15 Using the .45 Professional Cartridge", J. Taylor
Info on the Peak Strain meter. This is still supported, but not available.
Peak Strain Meter - Overview Q&A
Links to gun related products:
Shooter's Gunlinks GunHoo
Links to instrumentation, chronographs and pressure measurement products:
Links to mathematical modeling software:
- Matlab - The real thing, but expensive.
- Scilab - A free alternative to Matlab. Quite nice.
- Mathcad - Try find an old version 5.