Ballistics

[Radiohead]

I have a very good ballistics program to determine the trajectory of a bullet out of a rifle. The program has an extensive library of projectiles sorted by the bullet diameter, calibre, and brands.

Unfortunately, the application only covers rifle ammunition.

Anyone knows of a similar application for shotgun ballistic?

 

[sherlockbonez]

You want to calculate pellet drop? I think they'll run out of steam long before, but interested in what people find.

I think Bob brista's book covers drop a bit.

 

[catnthehatt]

I have a very good ballistics program to determine the trajectory of a bullet out of a rifle. The program has an extensive library of projectiles sorted by the bullet diameter, calibre, and brands.

Unfortunately, the application only covers rifle ammunition.

Anyone knows of a similar application for shotgun ballistic?

Quickload has sh0otgun data.
Cat

 

[Juster]

From 0 - 100 yards you are about Mach 1.2 - 0.9 with a 12ga slug. This is a sensitive region (see graph) and most computer programs have very few data points in that range, so they won't work well.
McCoy's book:
http://2.bp.########.com/_bP_PNTfFn9I/TPA-TjBeRwI/AAAAAAAAAN8/DKmC8v7VbjA/s1600/mach.png

Many programs store this graph as crude approximation. So the steep part isn't represented well.
Over Mach 1.4 is pretty much a straight line, so the programs are accurate there.

Typical 12ga. Foster slug BC approx. = 0.07 (The 200-yard slug gun has come of age!, Sports Afield, Inc. Jun 2002)
Winchester has drop data for slugs on their website, I would go with that.


You would need to know your muzzle velocity of course. BCs aren't going to vary so much with slugs of the same shape.

22LR has the same problem.

Here is the "GNU Exterior Ballistics Computer" source for G7:
case G7:
if (vp> 4200 ) { A = 1.29081656775919e-09; M = 3.24121295355962; }
else if (vp> 3000 ) { A = 0.0171422231434847 ; M = 1.27907168025204; }
else if (vp> 1470 ) { A = 2.33355948302505e-03; M = 1.52693913274526; }
else if (vp> 1260 ) { A = 7.97592111627665e-04; M = 1.67688974440324; }
else if (vp> 1110 ) { A = 5.71086414289273e-12; M = 4.3212826264889 ; }
else if (vp> 960 ) { A = 3.02865108244904e-17; M = 5.99074203776707; }
else if (vp> 670 ) { A = 7.52285155782535e-06; M = 2.1738019851075 ; }
else if (vp> 540 ) { A = 1.31766281225189e-05; M = 2.08774690257991; }
else if (vp> 0 ) { A = 1.34504843776525e-05; M = 2.08702306738884; }
break;

You have 3 points in the jiggly range around 1110fps, which isn't what you would like. 3 points between 1260 and 4200 is OKish with the flatter curve.

 

[sunray]

It's an apples and oranges thing. Shot doesn't fly like a rifle bullet. Nor at anywhere near the velocities.
Mind you, as a computer tech, who was shooting long before there was such a thing as a PC, I've never once met a programmer who understands how many variables are involved. A wooden stock that expands in wet weather, for example. Ballistics programs just can't and don't cover every one of 'em.