**ballisticsresearch.net**

**The
research data is organized under calibre, then by bullet and within
that the firing series.**

**Use
the hyperlinks below to view the data. Since most of this is in the
form of Tables or Graphs, you will need to use the <BACK function
in your browser to return to this page.**

**9mm
Parabellum, 9x19, (Luger):**

**125
Grain Howitzer Lead Round-Nosed Bullet**

**The
research data tables for Series
1 & Series
2 show values for the Ballistic Coefficient, C, computed using the
Space Functions found in the American Ingalls' Tables. This is an
extremely laborious process and is shown for interest sake and because
it permits comparison with values of C computed using computer
programs which calculates retardation and C directly from input values
for V, v & the distance, d, that the bullet travels between the
chronographs measuring these velocities. In this instance, a program,
#PBCv, using the British 1902-9 functions, for Retardation
of the Standard Projectile, was used to perform the calculations.**

**The
20 graphs, (some of them examples, perhaps, of what not to do
with trend-lines & their equations) are viewable in the economical
.gif format. You should be able to load the data from the tables into
an application on your computer in order to manipulate it and produce
your own graphs. Here are some pointers to a few of the graphs. Graph
15 shows a plot of Ballistic Coefficient over Final Velocity
(which is the velocity measured on the chronograph furthest form the
firing point). Note the very high value of C just above the velocity
of sound. It is almost as though the bullet was forced to travel
faster so that it would not break the sound barrier! The velocity of
sound being close to 1120 feet per second in these tests. At what
point the retardation of the projectile was affected by its approach
to the velocity of sound, it is impossible to say. Its retardation
could be constant, determined by its starting velocity, or it could be
that it decelerates less near 1120 fps. We need to place more
chronographs in the firing line! Who's up for it? Projectiles which
just become subsonic, seem to suffer from increased retardation,
having lower values of C. Retardation at many velocities is clearly
not explained by a simple, to us, series of 7 equations used in the
attempts to explain the retardation of those early Standard
Projectiles. ( If you plot the results of the Gâvre (G1 Projectile)
firings, how many & what functions, for which velocity ranges,
might you use to calculate R for that Standard Projectile? ) The
military have doubtless conducted extensive firings of projectiles of
interest to them, unfortunately, for the science of ballistics, most
such organizations are reluctant to make their ballistic research
public. Graph
4 shows Initial Velocity over Final Velocity, being remarkably
linear overall but with some noticeable anomalies. Graph
9 is a plot of the Retardation of the Standard Projectile, R, over
the retardation of the Test Projectile, r. Notice here how a 'canyon'
is formed by bullets which have very markedly different retardation
values, r, where the Standard Projectile retardation values, R, remain
much the same. Only those bullets with final velocities very close to
the velocity of sound are found within this gap. This may be more
obvious in Graph
6, where R is on the longer, X axis. Graphs, 18,
19
& 20,
of retardation, r, over velocity also seem to point to the existence
of velocity 'no-go areas', which result in a range of retardation
rates for projectiles traveling at essentially similar velocities. The
similarity in the pattern of points, in graphs 5, 6 and graphs 18
thru' 20, clearly demonstrate the extent to which R is a function of
velocity. Others may interpret some of these results in different
ways, hopefully someone can explain them? Can these results be
reproduced for other projectiles? Is there some harmonic of the
velocity of sound responsible for anomalies at other velocities? What
happens at twice or three times the velocity of sound? Can you help to
increase the body of knowledge in any of these areas?**

**9mm
125LRN Graphs: 1,
2,
3,
4,
5,
6,
7,
8,
9,
10,
11,
12,
13,
14,
15,
16,
17,
18,
19,
20.
**