## Introduction

This page offers different views of the FBI terminal ballistic testing data ("gelatin tests"). I started a discussion on The Firing Line, which is pretty interesting.

lbfps is momentum in units pound(mass)-feet-per-second.
ftlbs is energy in units foot-pounts(force).
cu is volume of wound cavity, in cubic inches.

Sorted by..
1. kinetic energy
2. momentum
3. (bare gelatin) penetration depth
4. (bare gelatin) wound volume
5. (clothed gelatin) penetration depth
6. (clothed gelatin) wound volume
7. Average wound volume for clothed and bare gelatin
Penetration over 30 inches in negatively sanctioned, and penetration over 20 inches is folded down to 20 inches.

#### Explanation of fields, example

```9x19    Win Ranger +P+  |115@1320, 21.7 mv, 444 E|BR  9.6", 0.53", 2.11cu|CL 10.2", 0.65", 3.37cu|avg 2.74, 3.89 re, 0.70
```
1. 9x19 - caliber
2. Win Ranger +P+ - the name of the load
3. 115@1320 - bullet mass in grains @ muzzle velocity
4. 21.7 mv - bullet momentum in lb*fps
5. 444 E - muzzle energy in ftlbs
6. BR - what follows is the data for bare gelatin
1. 9.6" inches of penetration
2. 0.53", final expanded diameter of bullet
3. 2.11 cu, approximation of wound volume. (this does not take into account the expansion profile as a function of depth, but it should be roughly proportionate to actual wound volume)
7. CL - what follows is the data for clothed gelatin
same fields as the bare gelatin, as defined above
8. avg 2.74 - Average wound volume, clothed and bare gelatin
9. 3.89 re - Free Recoil Energy, assuming a 1.88 lb pistol
10. 0.70 - Average would volume per unit Free Recoil Energy. This is a measure of "bang for buck", and is discussed in the text below the data table.
```Sorted by s_pen1
9x19    Hornady XTP     |147@ 918, 19.3 mv, 275 E|BR 22.1", 0.44", 3.36cu|CL 20.5", 0.46", 3.41cu|avg 3.18, 3.07 re, 1.04
10mm    Hornady XTP     |200@1056, 30.2 mv, 495 E|BR 21.4", 0.58", 5.65cu|CL 24.1", 0.52", 5.13cu|avg 4.77, 7.53 re, 0.63
9x19    Fed HydraShok   |147@ 995, 20.9 mv, 323 E|BR 21.4", 0.37", 2.30cu|CL 15.6", 0.60", 4.41cu|avg 3.28, 3.61 re, 0.91
40SW    Fed HydraShok   |165@ 943, 22.2 mv, 325 E|BR 18.2", 0.63", 5.69cu|CL 19.4", 0.56", 4.77cu|avg 5.23, 4.08 re, 1.28
9x19    Rem             |147@ 987, 20.7 mv, 318 E|BR 18.1", 0.51", 3.71cu|CL 15.9", 0.59", 4.36cu|avg 4.03, 3.55 re, 1.14
45ACP   Win             |230@ 802, 26.4 mv, 328 E|BR 17.9", 0.60", 5.06cu|CL 24.0", 0.51", 4.90cu|avg 4.57, 5.74 re, 0.80
40SW    Rem G.S.        |180@ 945, 24.3 mv, 356 E|BR 16.9", 0.64", 5.44cu|CL 21.0", 0.43", 3.05cu|avg 4.17, 4.88 re, 0.85
40SW    Rem G.S.        |180@ 931, 23.9 mv, 346 E|BR 16.8", 0.69", 6.28cu|CL 16.9", 0.63", 5.28cu|avg 5.78, 4.74 re, 1.22
45ACP   Fed HydraShok   |230@ 878, 28.8 mv, 393 E|BR 16.6", 0.66", 5.66cu|CL 20.2", 0.55", 4.80cu|avg 5.21, 6.88 re, 0.76
10mm    Norma           |170@1358, 33.0 mv, 695 E|BR 16.6", 0.59", 4.52cu|CL 17.0", 0.63", 5.30cu|avg 4.91, 8.99 re, 0.55
357MAG  Fed JHP         |158@1200, 27.1 mv, 505 E|BR 16.5", 0.50", 3.24cu|CL 15.9", 0.64", 5.12cu|avg 4.18, 6.07 re, 0.69
45ACP   Rem             |185@ 903, 23.9 mv, 335 E|BR 16.2", 0.70", 6.23cu|CL 24.6", 0.55", 5.83cu|avg 5.49, 4.71 re, 1.17
357SIG  CCI/Speer GD    |125@1372, 24.5 mv, 522 E|BR 16.1", 0.60", 4.54cu|CL 19.1", 0.54", 4.36cu|avg 4.45, 4.96 re, 0.90
45ACP   CCI/Speer GD    |230@ 896, 29.4 mv, 409 E|BR 16.0", 0.69", 5.98cu|CL 18.9", 0.59", 5.17cu|avg 5.58, 7.17 re, 0.78
40SW    Fed HydeaShok   |165@ 931, 21.9 mv, 317 E|BR 15.8", 0.58", 4.19cu|CL 21.1", 0.43", 3.06cu|avg 3.55, 3.98 re, 0.89
10mm    CCI/Speer PHP   |180@ 992, 25.5 mv, 393 E|BR 15.8", 0.72", 6.44cu|CL 17.5", 0.61", 5.11cu|avg 5.78, 5.38 re, 1.07
357MAG  Win Silvertip   |145@1166, 24.2 mv, 437 E|BR 15.8", 0.58", 4.17cu|CL 12.9", 0.64", 4.15cu|avg 4.16, 4.82 re, 0.86
40SW    Rem G.S.        |180@ 893, 23.0 mv, 318 E|BR 15.7", 0.65", 5.19cu|CL 21.1", 0.51", 4.32cu|avg 4.64, 4.36 re, 1.06
45ACP   Rem G.S.        |230@ 871, 28.6 mv, 387 E|BR 15.0", 0.71", 5.94cu|CL 18.9", 0.73", 7.89cu|avg 6.91, 6.77 re, 1.02
45ACP   Fed HydraShok   |230@ 854, 28.1 mv, 372 E|BR 14.9", 0.71", 5.90cu|CL 15.4", 0.64", 4.97cu|avg 5.43, 6.51 re, 0.83
9x19    Win Black Talon |147@ 946, 19.9 mv, 292 E|BR 14.8", 0.60", 4.20cu|CL 16.4", 0.61", 4.78cu|avg 4.49, 3.26 re, 1.38
9x19    CCI/Speer GD    |147@ 924, 19.4 mv, 278 E|BR 14.8", 0.57", 3.78cu|CL 14.7", 0.55", 3.49cu|avg 3.63, 3.11 re, 1.17
40SW    Rem G.S.        |180@ 954, 24.5 mv, 363 E|BR 14.8", 0.66", 5.06cu|CL 14.8", 0.67", 5.20cu|avg 5.13, 4.98 re, 1.03
40SW    Rem G.S.        |165@1022, 24.1 mv, 382 E|BR 14.8", 0.65", 4.89cu|CL 14.3", 0.66", 4.91cu|avg 4.90, 4.80 re, 1.02
40SW    Fed Hi-Shok     |180@ 960, 24.7 mv, 368 E|BR 14.8", 0.66", 5.05cu|CL 24.0", 0.47", 4.16cu|avg 4.26, 5.04 re, 0.85
9x19    Win Silvertip   |147@ 902, 18.9 mv, 265 E|BR 14.6", 0.53", 3.22cu|CL 18.1", 0.47", 3.14cu|avg 3.18, 2.97 re, 1.07
40SW    CCI/Speer GD    |180@ 958, 24.6 mv, 366 E|BR 14.6", 0.60", 4.13cu|CL 17.1", 0.62", 5.16cu|avg 4.65, 5.02 re, 0.93
40SW    Hornady XTP     |155@1194, 26.4 mv, 490 E|BR 14.5", 0.65", 4.81cu|CL 18.1", 0.55", 4.30cu|avg 4.56, 5.78 re, 0.79
40SW    CCI/Speer GD    |180@ 982, 25.3 mv, 385 E|BR 14.5", 0.59", 3.96cu|CL 17.6", 0.60", 4.96cu|avg 4.46, 5.27 re, 0.85
45ACP   Rem G.S.        |185@1037, 27.4 mv, 441 E|BR 14.4", 0.72", 5.86cu|CL 15.9", 0.68", 5.79cu|avg 5.83, 6.21 re, 0.94
357MAG  Rem G.S.        |125@1220, 21.8 mv, 413 E|BR 14.4", 0.56", 3.55cu|CL 20.6", 0.48", 3.72cu|avg 3.58, 3.92 re, 0.91
40SW    Fed HydraShok   |180@ 969, 24.9 mv, 375 E|BR 14.2", 0.69", 5.29cu|CL 19.8", 0.59", 5.41cu|avg 5.35, 5.13 re, 1.04
45ACP   Rem G.S.        |230@ 885, 29.1 mv, 399 E|BR 14.1", 0.76", 6.37cu|CL 16.6", 0.69", 6.19cu|avg 6.28, 6.99 re, 0.90
9x19    CorBon XTP      |124@1123, 19.9 mv, 347 E|BR 13.9", 0.56", 3.44cu|CL 18.3", 0.46", 3.04cu|avg 3.24, 3.27 re, 0.99
40SW    Hornady XTP     |180@ 929, 23.9 mv, 345 E|BR 13.9", 0.64", 4.49cu|CL 18.4", 0.55", 4.38cu|avg 4.44, 4.72 re, 0.94
45ACP   PMC/Eldorado SF |230@ 853, 28.0 mv, 371 E|BR 13.9", 0.67", 4.90cu|CL 22.6", 0.45", 3.59cu|avg 4.04, 6.49 re, 0.62
10mm    Win Black Talon |200@ 901, 25.7 mv, 360 E|BR 13.9", 0.67", 4.90cu|CL 15.6", 0.67", 5.50cu|avg 5.20, 5.48 re, 0.95
40SW    Fed HydraShok   |165@1007, 23.7 mv, 371 E|BR 13.8", 0.62", 4.18cu|CL 15.2", 0.64", 4.87cu|avg 4.53, 4.66 re, 0.97
45ACP   Fed HydraShok   |230@ 956, 31.4 mv, 466 E|BR 13.8", 0.72", 5.64cu|CL 13.6", 0.74", 5.83cu|avg 5.73, 8.16 re, 0.70
45ACP   Fed Hi-Shok     |230@ 860, 28.3 mv, 377 E|BR 13.8", 0.80", 6.96cu|CL 17.4", 0.67", 6.13cu|avg 6.55, 6.60 re, 0.99
9x19    Win Ranger Talon|147@ 864, 18.1 mv, 243 E|BR 13.8", 0.61", 4.03cu|CL 15.2", 0.59", 4.17cu|avg 4.10, 2.72 re, 1.51
9x19    Win Ranger T    |147@1016, 21.3 mv, 337 E|BR 13.8", 0.66", 4.72cu|CL 15.7", 0.66", 5.37cu|avg 5.05, 3.76 re, 1.34
9x19    Win Ranger Talon|147@1017, 21.4 mv, 337 E|BR 13.8", 0.66", 4.70cu|CL 15.5", 0.65", 5.14cu|avg 4.92, 3.77 re, 1.31
40SW    Fed Hi-Shok     |155@1167, 25.8 mv, 468 E|BR 13.8", 0.61", 4.02cu|CL 19.5", 0.51", 3.98cu|avg 4.00, 5.52 re, 0.72
40SW    Win Ranger T.   |180@ 947, 24.4 mv, 358 E|BR 13.8", 0.69", 5.14cu|CL 13.7", 0.70", 5.25cu|avg 5.20, 4.90 re, 1.06
45ACP   Fed HydraShok   |230@ 858, 28.2 mv, 375 E|BR 13.7", 0.71", 5.42cu|CL 16.4", 0.66", 5.59cu|avg 5.51, 6.57 re, 0.84
9x19    Fed HydraShok   |147@ 935, 19.6 mv, 285 E|BR 13.6", 0.60", 3.85cu|CL 16.1", 0.52", 3.41cu|avg 3.63, 3.19 re, 1.14
40SW    Win Ranger T    |180@ 943, 24.2 mv, 355 E|BR 13.6", 0.68", 4.94cu|CL 14.6", 0.70", 5.62cu|avg 5.28, 4.86 re, 1.09
40SW    Win Ranger Talon|180@1000, 25.7 mv, 399 E|BR 13.6", 0.68", 4.92cu|CL 13.5", 0.68", 4.90cu|avg 4.91, 5.47 re, 0.90
40SW    Win B.T.        |180@ 917, 23.6 mv, 336 E|BR 13.5", 0.69", 5.05cu|CL 14.4", 0.70", 5.54cu|avg 5.29, 4.60 re, 1.15
9x19    CCI/Speer GD +P |124@1223, 21.7 mv, 411 E|BR 13.4", 0.68", 4.87cu|CL 20.2", 0.53", 4.47cu|avg 4.64, 3.88 re, 1.20
45ACP   Fed Hi-Shok     |185@ 953, 25.2 mv, 373 E|BR 13.3", 0.63", 4.15cu|CL 12.4", 0.74", 5.33cu|avg 4.74, 5.24 re, 0.90
45ACP   Win Ranger SXT  |230@ 819, 26.9 mv, 342 E|BR 13.2", 0.73", 5.55cu|CL 17.9", 0.63", 5.56cu|avg 5.55, 5.99 re, 0.93
9x19    CCI/Speer GD+P  |124@1155, 20.5 mv, 367 E|BR 13.2", 0.62", 3.99cu|CL 16.1", 0.53", 3.55cu|avg 3.77, 3.46 re, 1.09
45ACP   CCI/Speer GD    |230@ 847, 27.8 mv, 366 E|BR 13.2", 0.74", 5.66cu|CL 14.3", 0.70", 5.50cu|avg 5.58, 6.40 re, 0.87
40SW    Rem G.S.        |165@ 952, 22.4 mv, 332 E|BR 13.1", 0.64", 4.21cu|CL 20.0", 0.53", 4.41cu|avg 4.31, 4.16 re, 1.04
40SW    Win Ranger PG   |165@1109, 26.1 mv, 450 E|BR 13.1", 0.73", 5.48cu|CL 14.5", 0.72", 5.90cu|avg 5.69, 5.65 re, 1.01
40SW    CCI/Speer GD    |165@1076, 25.4 mv, 424 E|BR 13.1", 0.65", 4.33cu|CL 15.8", 0.60", 4.47cu|avg 4.40, 5.32 re, 0.83
45ACP   CCI/Speer GD'   |230@ 896, 29.4 mv, 409 E|BR 13.0", 0.71", 5.16cu|CL 13.6", 0.69", 5.11cu|avg 5.14, 7.17 re, 0.72
9x19    CCI/Speer GD    |115@1197, 19.7 mv, 365 E|BR 12.8", 0.67", 4.51cu|CL 22.6", 0.44", 3.44cu|avg 3.78, 3.20 re, 1.18
9x19    CCI/Speer GD    |124@1068, 18.9 mv, 314 E|BR 12.6", 0.59", 3.44cu|CL 17.5", 0.51", 3.57cu|avg 3.51, 2.96 re, 1.19
9x19    Win Ranger PG   |124@1015, 18.0 mv, 283 E|BR 12.5", 0.65", 4.15cu|CL 14.0", 0.61", 4.09cu|avg 4.12, 2.67 re, 1.54
40SW    Rem             |165@1031, 24.3 mv, 389 E|BR 12.5", 0.67", 4.41cu|CL 16.3", 0.61", 4.76cu|avg 4.59, 4.88 re, 0.94
9x19    Rem             |124@1109, 19.6 mv, 338 E|BR 12.4", 0.60", 3.52cu|CL 13.7", 0.57", 3.50cu|avg 3.51, 3.19 re, 1.10
9x19    CCI/Speer GD    |115@1259, 20.7 mv, 404 E|BR 12.3", 0.67", 4.35cu|CL 22.1", 0.40", 2.78cu|avg 3.43, 3.54 re, 0.97
40SW    Win Silvertip   |155@1199, 26.5 mv, 494 E|BR 12.2", 0.69", 4.54cu|CL 13.2", 0.71", 5.21cu|avg 4.87, 5.83 re, 0.84
45ACP   CCI/Speer GD    |185@1041, 27.5 mv, 445 E|BR 11.9", 0.68", 4.34cu|CL 14.8", 0.68", 5.36cu|avg 4.85, 6.26 re, 0.77
45ACP   Win. B.T.       |230@ 886, 29.1 mv, 400 E|BR 11.9", 0.77", 5.56cu|CL 13.9", 0.74", 6.00cu|avg 5.78, 7.01 re, 0.83
9x19    CCI/Speer GD    |124@1116, 19.8 mv, 342 E|BR 11.8", 0.69", 4.41cu|CL 22.0", 0.36", 2.24cu|avg 3.22, 3.23 re, 1.00
45ACP   Fed Hi-Shok     |185@ 874, 23.1 mv, 313 E|BR 11.7", 0.74", 5.03cu|CL 19.8", 0.61", 5.79cu|avg 5.41, 4.41 re, 1.23
45ACP   CCI/Speer GD +P |200@1062, 30.3 mv, 500 E|BR 11.7", 0.75", 5.17cu|CL 18.8", 0.55", 4.47cu|avg 4.82, 7.61 re, 0.63
9x19    3-D             |115@1178, 19.4 mv, 354 E|BR 11.6", 0.54", 2.66cu|CL 13.9", 0.48", 2.52cu|avg 2.59, 3.10 re, 0.84
.380    CCI/Speer GD    | 88@ 914, 11.5 mv, 163 E|BR 11.6", 0.46", 1.92cu|CL 17.2", 0.35", 1.66cu|avg 1.79, 1.09 re, 1.64
9x19    Fed +P          |115@1237, 20.3 mv, 390 E|BR 11.2", 0.53", 2.48cu|CL 10.6", 0.62", 3.20cu|avg 2.84, 3.41 re, 0.83
40SW    Win Ranger SXT  |180@ 905, 23.3 mv, 327 E|BR 11.2", 0.70", 4.31cu|CL 13.0", 0.64", 4.18cu|avg 4.25, 4.48 re, 0.95
9x19    Rem +P+         |115@1221, 20.1 mv, 380 E|BR 10.8", 0.63", 3.37cu|CL 10.9", 0.62", 3.29cu|avg 3.33, 3.33 re, 1.00
40SW    CCI/Speer GD    |155@1176, 26.0 mv, 475 E|BR 10.7", 0.84", 5.93cu|CL 18.1", 0.57", 4.62cu|avg 5.27, 5.61 re, 0.94
40SW    CCI/Speer GD    |155@1186, 26.3 mv, 483 E|BR 10.7", 0.84", 5.93cu|CL 17.7", 0.58", 4.68cu|avg 5.30, 5.70 re, 0.93
45ACP   Win Silvertip   |185@ 951, 25.1 mv, 371 E|BR 10.7", 0.78", 5.11cu|CL 10.9", 0.73", 4.56cu|avg 4.84, 5.22 re, 0.93
45ACP   CCI/Speer GD'   |185@1041, 27.5 mv, 445 E|BR 10.7", 0.83", 5.74cu|CL 12.6", 0.74", 5.40cu|avg 5.57, 6.26 re, 0.89
9x19    PMC/Eldorado SF |124@1118, 19.8 mv, 344 E|BR 10.7", 0.63", 3.32cu|CL 20.1", 0.41", 2.65cu|avg 2.98, 3.24 re, 0.92
357MAG  Fed JHP         |125@1265, 22.6 mv, 444 E|BR 10.7", 0.49", 2.01cu|CL 11.8", 0.51", 2.40cu|avg 2.20, 4.22 re, 0.52
45ACP   CCI/Speer GD +P'|200@1062, 30.3 mv, 500 E|BR 10.3", 0.82", 5.44cu|CL 12.4", 0.73", 5.15cu|avg 5.30, 7.61 re, 0.70
45ACP   Rem G.S. +P     |185@1046, 27.6 mv, 449 E|BR 10.1", 0.87", 6.00cu|CL  9.5", 0.81", 4.90cu|avg 5.45, 6.32 re, 0.86
9x19    Fed Silvertip   |115@1091, 17.9 mv, 304 E|BR 10.1", 0.63", 3.13cu|CL 11.8", 0.58", 3.12cu|avg 3.13, 2.66 re, 1.18
9x19    Win Ranger +P+  |115@1320, 21.7 mv, 444 E|BR  9.6", 0.53", 2.11cu|CL 10.2", 0.65", 3.37cu|avg 2.74, 3.89 re, 0.70
.380    CCI/Speer GD    | 90@ 934, 12.0 mv, 174 E|BR  9.3", 0.59", 2.54cu|CL 11.3", 0.49", 2.14cu|avg 2.34, 1.19 re, 1.96
9x19    CorBon +P       |115@1317, 21.6 mv, 442 E|BR  8.9", 0.52", 1.90cu|CL 10.2", 0.61", 2.98cu|avg 2.44, 3.87 re, 0.63
.380    Win Silvertip   | 85@ 954, 11.6 mv, 172 E|BR  7.9", 0.58", 2.09cu|CL  9.1", 0.47", 1.58cu|avg 1.83, 1.11 re, 1.65
.380    Fed HydraShok   | 90@ 971, 12.5 mv, 188 E|BR  6.7", 0.66", 2.29cu|CL 12.0", 0.49", 2.26cu|avg 2.28, 1.29 re, 1.77
```

## Discussion

### Background

I have virtually the "same" handgun in three calibers: a Glock 19 (9x19), 32 (.357SIG), and "virtual" 23 (.40SW). I am intrigued by the difference in ballistics - terminal and external - of these rounds.

The FirearmsTactical web site has a large library of terminal ballistics data from the FBI tests. As far as I've been able to figure out, the FBI tests are done as follows:

1. 1. Fire test rounds into both bare and "clothed" gelatin blocks. The gel blocks have been calibrated so that they have a standard consistency.
2. Measure the maximum penetration, and
3. Retrieve the expanded round and measure its expansion.

The data ends up looking like this: 9mm 124 grain CCI/Speer Gold Dot JHP +P, 4/17/97, Test gun SIG P226, Barrel length 4.25", Velocity 1223 fps, Bare gelatin penetration 13.4", expansion 0.68", Clothed gelatin 20.25", expansion 0.53".

So, my question is, what is the best way to compare the results? Obviously you want attain a certain penetration depth (what the minimum is is debatable), and you want the round to expand sufficiently. We can compare max. penetration, or expansion, or penetration * expansion, which should approximate the total volume of destroyed, err, "gel." Or we could use some other comparision. It would seem more useful to compare the "clothed" gelatin results, since people usually wear clothes.

So, just what is the best way to compare them?

For those who are wondering where I'm going.. We always have discussions like: W has more energy! X has more momentum! Y has more penetration! Z has more expansion!

In my opinion, the gelatin tests would seem to translate much more directly to real-world results than a more abstract measure such as energy, since they have to do with real physical effects. Once I have a way to compare the results of the FBI tests, I can see which particular computed metrics correlate with those results.

### "Stopping power" mechanisms

If we want to study how "stopping" or incapacitating takes places, we need to know the physical mechanisms that occur that effect the stop. Furthermore, we should be able to measure those mechanisms. Once we understand the mechanisms of stopping or incapacitating, we can create a test which can measure one or more of those effects in a test material. If done carefully, we can be assured that a result of X in the test media will map to result X in an assailent. Repeat for all the known mechanisms.

The problem with many "stopping power" metrics is that they are either too abstract, biased, or not connected with any physical effect related to "stopping".

By "abstract", I mean things like kinetic energy or momentum. We have arguments like "light and fast" vs. "big and slow." Without any more data, these particular arguments are not based on physical effects.

By "biased", I mean the metric is based on a data collection methodology that is inherently flawed. The recent thread on the M&S OSS numbers brought to light some serious problems with that metric.

Finally, by "not connected with any physical effect related to 'stopping'", I mean things we talk about for which there is no known mechanism linking them to incapacitation. It is possible that "energy dump", to the extent that it does not induce tissue damage, is in this category.

Terminal performance is very linked to bullet design, also. A good test must take this into account.

I think the FBI data may be valuable because:

1. it's "scientific" in that it's published, reliable, repeatable, and not biased by sampling,
2. it measures several things very likely directly linked to one of the incapacitating mechanisms (penetration and expansion / wound volume). I have high confidence that this is one such mechanism because more damaged tissue means more blood loss and more mechanical incapacitation in the case of muscle damage.
Problems with the FBI data:
1. . it only has one point per load. It would be more interesting if we had a statistically-valid sample from each load / gun, so we knew standard deviation.
2. it would be more interesting to test the same bullet's terminal performance at a range of velocities.
3. we do not know the expansion profile, as a function of penetration depth. If we knew this, we could compute actual wound volume.

I agree that the old, sage advice of "Pick the most powerful caliber you can shoot well in your gun, and use premium bullets" is excellent when considering personal caliber and firearm choice. I feel adequately armed with a good load in 9mm, .40, 357SIG, or .45, but that doesn't mean we should not understand how incapacitation works, which loads perform, and why.

### Conclusions

Staring at the different views of the data - primarily sorted by bare and clothed wound volume - made me notice a few things, some obvious, some not:

1. terminal performance can be a lot different for a round in bare vs. clothed gelatin,
2. small, fast rounds that depend on lots of expansion to get wound volume (or width) can often be foiled by clothing (e.g.: .40 CCI/Speer GD 155gr: bare, it expanded by 110%, to 0.84, but in clothed gelatin, it only expanded by 54%),
3. bullets that start out smaller must expand to a larger percentage of their original size than a larger bullet to attain the same wound width,
4. less massy bullets have less "material" to work with in terms of expansion - they are stretched "more thin",
5. heavier, slower rounds in .40 (or 10mm) and .45 did extremely well in bare gelatin wound volume, but they ruled clothed gelatin wound volume. Their slow velocity did not prevent expansion. e.g.: the 230gr Rem Golden Saber .45 ACP at 871 fps expanded 58% in bare, and 62% in clothed gelatin!
6. the best 9mm rounds tested, according to wound volume in both cases, are the: CCI/Speer Gold Dot 124 +P, and the 147gr Black Talon. This made me re-evaluate my "carry" choice in 9mm, since it was a Proload/GD 115+P. I switched to 124+P.
7. the best .45ACP loads and the best .40 loads were pretty close. "heavy" 9mm's were noticably behind. "light" 9mm's were last,
8. while some 9mm 115's did well relative to the 124gr's and 147gr's in bare gelatin, they scored the worst in clothed gelatin,
9. 357SIG performs similarly to CCI/Speer GD 124 +P. The extra 100 fps didn't help much, either in penetration or wound volume.
10. pick a caliber you like, and then research the best bullet for your platform, since the particular load makes a much bigger difference than caliber in some cases (e.g.: a 9mm beating a .45),
11. stated another way, there are some general trends in terms of wound volume by caliber, but there is significant overlap based on particular load performance,
12. if a round fails to expand "normally" from clothing, there is a good chance it will over-penetrate.. sort by "(clothed gelatin) penetration depth" and notice how many are over 20" penetration,

The big caveat in these conclusions is that they are just one data point per load, and most of the data is pretty old. I wonder if some new loads would perform differently - e.g. would a 357SIG at 1450 FPS perform much better than this one at 1372fps?

### Supporting opinions

quote:

Kinetic energy does not wound. Temporary cavity does not wound. The much discussed
"shock" of bullet impact is a fable and "knock down" power is a myth. The critical
element is penetration. The bullet must pass through the large, blood bearing organs
and be of sufficient diameter to promote rapid bleeding. Penetration less than 12
inches is too little, and, in the words of two of the participants in the 1987 Wound
Ballistics Workshop, "too little penetration will get you killed." 42,43 Given desirable
and reliable penetration, the only way to increase bullet effectiveness is to increase
the severity of the wound by increasing the size of hole made by the bullet. Any bullet
which will not penetrate through vital organs from less than optimal angles is not
acceptable. Of those that will penetrate, the edge is always with the bigger bullet.44

### Subjective Factors

One reason many cite for shooting 9x19 over .40 or .45 is that is has less recoil. I can empty my Glock 19's magazine into a 3" target much faster than I can my Glock 23. Maybe twice as fast.

I know that perceived recoil depends a lot on the profile of the recoil impulse, and it should also depend on the momentum of the bullet.

For back-of-the-envelope calculations, I have been using bullet momentum in lb(mass)*fps(velocity). This should be proportional to total absorbed recoil energy in the same gun platform (eg: Glock 19/23/32).

If I do this simple comparison:

```9x19,   115   @ 1200, mv = 19.7
9x19,   124   @ 1100, mv = 19.8, basic load
9x19,   124+P @ 1200, mv = 21.7, +9.5%

357SIG, 125   @ 1372, mv = 24.5, +23.7%

40SW,   180   @  982, mv = 25.3. +27.7%
40SW,   165   @ 1076, mv = 25.4, +28.3%
40SW,   155   @ 1180, mv = 26.2, +32.3%
40SW,   135   @ 1250, mv = 24.1, +21.7%

45ACP,  230   @  847, mv = 27.8, +40.4%
45ACP,  200+P @ 1062, mv = 30.3, +53.0%
45ACP,  185   @ 1041, mv = 27.5, +38.8%
```
The pecentages represent how much more recoil the load has than 9x19, 124gr @ 1100fps. This only takes into account total momentum transfer, not the "sharpness" of the recoil impulse. That would most likely be proportional to muzzle energy.

An individual has to choose the most effective defense package, taking into account both the expected terminal ballistics of the round and caliber he chooses and how well he shoots that pistol and ammunition combination. For example, if a person were trying to decide between shooting 9x19 or .40SW, he might:

1. from a holster, at 7 yards,
2. shoot ten rounds into an NRA-type pistol target as quickly as possible,
3. do this for both pistols, and
4. score the targets, scale the score to percent,
5. multiply the FBI wound volume for each round by the target's score, and
6. divide that by the time it took to shoot the rounds, starting from the holster.

This kind of a calculation is going to yield something like total wound volume (in cubic inches) per second. It will take into account if a person is slower and less accurate with a certain pistol and caliber, and it will take into account the terminal ballistics of the round.

The pistol and caliber with the highest score wins.

[Zak Smith] [zak@computer.org] [/~zak/firearms/fbi-pistol.php?sort=pen1]
\$Id: fbi-pistol.php,v 1.1 2001/08/18 18:49:46 zak Exp zak \$