.45 ACP - Performance

Performance

The .45 ACP is an effective combat pistol cartridge that combines accuracy and stopping power for use against human targets. The cartridge also has relatively low muzzle blast and flash, as well as moderate recoil. The .45 ACP also operates at a relatively low maximum chamber pressure rating of 21,000 psi (145 MPa) (compared to 35,000 psi/240 MPa for 9mm Parabellum and .40 S&W, 37,500 psi/260 MPa for 10mm Auto, 40,000 psi/280 MPa for .357 SIG), which due to a low bolt thrust helps extend service life of weapons in which it is fired.

Like many pistol cartridges, it is a low-velocity round, and thus ineffective against body armor. Another drawback for large scale military operations is the cartridge's large size, weight, and the increased material cost of manufacture compared to the smaller 9×19mm Parabellum cartridge.

Even in its non-expanding full metal jacket (FMJ) version, the .45 ACP cartridge has a reputation for effectiveness against human targets because its large diameter creates a deep and substantial permanent wound channel which lowers blood pressure more rapidly. The wounding potential of bullets is often characterized in terms of a bullet's expanded diameter, penetration depth, and energy. Bullet energy for .45 ACP loads varies from roughly 350 to 500 ft·lbf (470 to 680 J). ATOMIC Ammunition produces a new load that pushes a 185 grain copper bonded hollow point bullet to 1225 feet per second and achieves over 616 foot pounds of energy. This load safely conforms to SAAMI specifications for 45 ACP+P and outperforms certain 10mm and 357 Magnum loads by other manufacturers.

The table below shows common performance parameters for several .45 ACP loads. Bullet weights ranging from 185 to 230 grains are common, and bullets as light as 125 grains exist, as well as a 255 grain hardcast made by Buffalo Bore. Penetration depths from 11 inches to over 27 inches are available for various applications and risk assessments.

Manufacturer Load Mass Velocity Energy Expansion Penetration PC TSC
ATOMIC AMMUNITION Bonded Match Hollow Point 15 g (230 gr) 300 m/s (1,000 ft/s) 690 J (510 ft·lb) 21 mm (0.82 in) 410 mm (16.0 in) 0 mL (0 cu in) 0 mL (0 cu in)
Federal HydraShok JHP 15 g (230 gr) 260 m/s (850 ft/s) 500 J (369 ft·lb) 20 mm (0.78 in) 300 mm (12.0 in) 93.9 mL (5.73 cu in) 465 mL (28.4 cu in)
Remington Golden Saber JHP 15 g (230 gr) 267 m/s (875 ft/s) 530 J (391 ft·lb) 19 mm (0.75 in) 360 mm (14.3 in) 103.6 mL (6.32 cu in) 416 mL (25.4 cu in)
ATOMIC Ammunition Bonded Match Hollow Point 12.0 g (185 gr) 373 m/s (1,225 ft/s) 835 J (616 ft·lb) 21 mm (0.82 in) 410 mm (16.0 in) 0 mL (0 cu in) 0 mL (0 cu in)
Cor-Bon JHP 12.0 g (185 gr) 350 m/s (1,150 ft/s) 738 J (544 ft·lb) 18 mm (0.7 in) 290 mm (11.3 in) 71.3 mL (4.35 cu in) 469 mL (28.6 cu in)
Winchester Silvertip JHP 12.0 g (185 gr) 300 m/s (1,000 ft/s) 557 J (411 ft·lb) 20 mm (0.79 in) 300 mm (12.0 in) 96.4 mL (5.88 cu in) 495 mL (30.2 cu in)
Winchester Ranger SXT 15 g (230 gr) 270 m/s (900 ft/s) 561 J (414 ft·lb) 20 mm (0.78 in) 330 mm (13 in) 101.8 mL (6.21 cu in) 416 mL (25.4 cu in)
Remington FMJ 15 g (230 gr) 255 m/s (835 ft/s) 483 J (356 ft·lb) 11 mm (0.45 in) 690 mm (27 in) 70.3 mL (4.29 cu in) 150 mL (9 cu in)

Key:
Expansion: expanded bullet diameter (ballistic gelatin).
Penetration: penetration depth (ballistic gelatin).
PC: permanent cavity volume (ballistic gelatin, FBI method).
TSC: temporary stretch cavity volume (ballistic gelatin).
(gr for grains, and g for grams)

The .45 ACP's combination of stopping power and controlled penetration makes it practical for police use, although numerous issues, including the resulting decrease in magazine capacity and the larger size and weight of pistols chambered in this caliber, have led more police departments in the USA to adopt sidearms in 9×19mm, .40 S&W, and .357 SIG. With standard (not extended) single-stack magazines, pistols chambered in .45 ACP usually hold 8 rounds or less (an exception to this is the .45 ACP version of the Smith & Wesson SW99, which holds 9). However, many modern versions of .45 ACP handguns have double-stack magazines capable of holding as many as 14 cartridges, such as the HS2000, and the FN FNP-45 Competition (standard barrel) and Tactical (threaded barrel) both hold 15, though this greatly increases the pistol's bulk and with that lowers maneuverability.

Many US tactical police units still use the .45 pistol round, including the FBI's Hostage Rescue Team. While high capacity firearms are available in .45 ACP, the greater length and diameter of the .45 ACP means that the grip of the pistol must be longer and wider than the grip of a comparable pistol of a smaller caliber; this increase in grip size can make the pistol difficult to use for shooters with smaller hands.

Today, most NATO militaries use sidearms chambered for the 9×19mm Parabellum cartridge, but the effectiveness of the .45 ACP cartridge has ensured its continued popularity with large caliber sport shooters, especially in the United States. In addition, select military and police units around the world still use firearms firing the .45 ACP. In 1985, the .45 ACP M1911A1 pistol was replaced by the Beretta M9 9mm pistol as the main sidearm of the U.S. military, although select Special Operations units continue to use the M1911A1 or other .45 ACP pistols.

Because standard pressure and load .45 ACP rounds fired from handguns or short barreled submachine guns are inherently subsonic, it is one of the most powerful pistol calibers available for use in suppressed weapons since subsonic rounds are quieter than supersonic rounds. The latter inevitably produce a highly compressed shock wave, audible as a loud "crack", literally a small sonic boom, while they travel through the air. Suppressors reduce the audible "report" by slowing and channeling the high speed gas generated by the burning/expanding gunpowder before it exits the muzzle resulting in a muffled "cough". Suppressors cannot act on a supersonic shock wave continuously generated by a bullet exceeding the 1,100 ft/s (340 m/s) speed of sound, as this shock wave is continuously produced throughout the entire flight path over which the bullet is supersonic, which extends long after it exits the barrel. The downside to the use of .45 ACP in suppressed weapons is that increasing the diameter of the passage through a suppressor decreases the suppressor's efficiency; thus, while .45 ACP is among the most powerful suppressed pistol rounds, it is also one of the loudest. Most .45 suppressors must be fired "wet" (with an ablative medium, usually water) to bring sound levels down to "hearing-safe" (under 140 dB, generally).

The maximum travelling range of a .45 caliber bullet was shown to be approximately 360 feet downrange, according to a Mythbusters episode.

Read more about this topic:  .45 ACP

Famous quotes containing the word performance:

    O world, world! thus is the poor agent despised. O traitors and bawds, how earnestly are you set a-work, and how ill requited! Why should our endeavour be so loved, and the performance so loathed?
    William Shakespeare (1564–1616)

    The honor my country shall never be stained by an apology from me for the statement of truth and the performance of duty; nor can I give any explanation of my official acts except such as is due to integrity and justice and consistent with the principles on which our institutions have been framed.
    Andrew Jackson (1767–1845)

    Just as the performance of the vilest and most wicked deeds requires spirit and talent, so even the greatest demand a certain insensitivity which under other circumstances we would call stupidity.
    —G.C. (Georg Christoph)