.220 Swift

.220 Swift
.220 Swift (center) with .223 Rem (left) and .308 Win (right).
Type	Rifle
Place of origin	United States
Production history
Designer	Winchester
Designed	1935
Manufacturer	Winchester
Produced	1935
Variants	Wilson-Wotkyns .220 Arrow[1]
Specifications
Parent case	6mm Lee Navy
Case type	Semi-rimmed, bottleneck
Bullet diameter	.224 in (5.7 mm)
Neck diameter	.260 in (6.6 mm)
Shoulder diameter	.402 in (10.2 mm)
Base diameter	.445 in (11.3 mm)
Rim diameter	.473 in (12.0 mm)
Case length	2.205 in (56.0 mm)
Overall length	2.680, 2.580 H.P. Bullets
Case capacity	47 gr H2O (3.0 cm3)
Rifling twist	1 in 14–16 in (360–410 mm)
Primer type	Large rifle
Maximum pressure	62,000 psi (430 MPa)
Ballistic performance
Bullet weight/type Velocity Energy 40 gr (3 g) HP 4,213 ft/s (1,284 m/s) 1,577 ft·lbf (2,138 J) 50 gr (3 g) SP 3,947 ft/s (1,203 m/s) 1,730 ft·lbf (2,350 J) 55 gr (4 g) SP 3,839 ft/s (1,170 m/s) 1,800 ft·lbf (2,400 J) 60 gr (4 g) SP 3,647 ft/s (1,112 m/s) 1,772 ft·lbf (2,403 J)
Source(s): Hodgdon[2]

The .220 Swift (5.56×56mmSR) is a semi-rimmed rifle cartridge developed by Winchester and introduced in 1935. It remains the first factory loaded rifle cartridge with a muzzle velocity of over 4,000 ft/s (1,200 m/s).^[3] the .220 Swift remains the fastest commercial cartridge in the world. with a published velocity of 4665 fps using a 29 grain bullet and 42 grains of 3031 powder. Despite the claim that the .223 WSSM is now the fastest production .22 caliber cartridge. The .220 swift still reigns supreme.^[4]

The Swift is a large cased .224 caliber cartridge and bullet that was created for small game such as prairie dogs, groundhogs and other vermin (or "varmints" in the US) such as marmots. Upon its introduction it astounded the varmint hunting world by being fully 1,400 ft/s (430 m/s) faster than its nearest competitor, which was the .22 Hornet (also .224 caliber).^[5] It was found to be an extremely accurate cartridge as well.^[6][7]

Due to its very high velocity its bullet drop allows dead on sighting on game such as groundhogs to ranges out to 375 yd (343 m), and it is still considered an excellent cartridge for taking varmints by experienced Swift shooters.^[6]

The original factory load from Winchester provided a 48-grain (3.1 g) bullet launched at 4,100 feet per second (1,250 m/s). Handloaders could marginally improve on this but only at maximum loads. The Swift can be loaded with light bullets to reach 4,400 ft/s (1,300 m/s).^[8] In recent times 75-grain (4.9 g) .224" bullets have been developed for use in high velocity .22 caliber rifles for taking larger game and long-distance shooting. Heavier bullets perform best in rifles that have an appropriate rifling twist rate taking into consideration the diameter, length, and other physical properties of the projectile.

History

The prototype for the .220 Swift was developed in 1934–35 by Grosvenor Wotkyns who necked down the .250-3000 Savage as a means of achieving very high velocities. However the final commercial version developed by Winchester is based on the 6mm Lee Navy cartridge necked down. The .220 Swift was developed by Winchester and introduced in 1935 as a new caliber for their Model 54 bolt-action rifle. When the Winchester Model 70 bolt action was first issued in 1936, the .220 Swift was one of the standard calibers offered and continued to be until 1964 when it was discontinued.^[6]

Acceptance

The Swift has the dubious privilege of being possibly the most controversial of all the many .224 in caliber cartridges,^[9] and has inspired equal heights of praise and criticism. Traditionalists have roundly condemned it as an overbore "barrel burner" which can wear out a chromoly barrel in as few as 200–300 rounds, especially if long strings of shots are fired from an increasingly hot barrel.^[10] Its supporters have maintained that the fault lies with poor-quality barrel steels and the failure of users to remove copper fouling after firing, and point to instances of rifles with fine-quality stainless steel barrels chambered for the Swift, which have maintained sub-MOA precision after well in excess of 4,000 shots.^[11]

Performance is currently matched by the newer .223 WSSM but the Swift remains more popular. Even more popular however is the smaller, and slightly lower velocity .22–250.^[12]

.220 Swift maximum C.I.P. cartridge dimensions. All sizes in millimeters (mm) plus Imperial (inches).

Drawbacks

The Swift's high-velocity performance comes at a price, because the high velocities and high internal firing temperatures accelerate chamber and bore wear.^[6] Modern metallurgy and cryogenic treatment have vastly improved barrel life with the .220 Swift and other 4,000 ft/s (1,200 m/s) cartridges, although weapons firing these cartridges still usually require rechambering or rebarreling much sooner than those firing lower-velocity cartridges such as the .222 Remington and the .223 Remington.

Hunting controversy

The Swift remains a controversial deer caliber. Its use is prohibited in many US states and also in the Netherlands, England, Wales and Northern Ireland for large deer such as Red, Sika and Fallow, but some states, such as Minnesota, currently allow smaller caliber rounds like the .220 Swift to be used. In the cartridge's early days during the 1930s, expert red deer stalkers such as W.D.M. Bell, the recently retired African elephant hunter, used the .220 Swift on large stags with great success, and extolled the caliber's seemingly magical killing powers, which they attributed to massive hydrostatic shock waves set up in the animal's body by the impact of the very high-velocity bullet.^[13]

Critics of the Swift have maintained that the light 50-or-55-grain (3.2 or 3.6 g) bullet leaves inadequate margin for error in bullet placement for the average deer shooter's skills, and thus invites wounding, which would have otherwise been avoidable. There is, however, little debate about the Swift's proven effectiveness on small deer species, such as Roe, provided very fast-fragmenting "varmint"-type bullets are not used.

Most factory Swift rifles come with a fairly slow twist-rate such as 1–12" or 1–14", designed to stabilize the lighter bullets popular in varmint hunting. Custom Swifts can have faster twist-rates such as 1–9" allowing them to stabilize heavy bullets, including those with a construction suitable for larger game.^[14][15]

P.O. Ackley maintained that the .220 Swift was a fine round for medium-large game and used it extensively for example when culling wild burros in the American West.^[16]

See also

• 5 mm caliber, other cartridges of 5–6 mm (.200–.236 in) caliber.
• Delta L problem
• List of rifle cartridges
• Table of handgun and rifle cartridges
• Varmint rifle

References

Winchester firearms and cartridges Rifles Lever-action Henry rifle Model 1866 Model 1873 Model 1876 Model 1886 Model 1892 Model 1894 Model 1895 Model 53 Model 55 Model 64 Model 65 Model 71 Model 88 Model 150 Model 250 Model 255 Model 9422 Bolt-action Model 1878 Hotchkiss Model 1895 Lee Navy Model 1900 Model 1902 Model 1904 Model 43 Model 47 Model 51 Imperial Model 52 Model 54 Model 56 Model 57 Model 58 Model 59 Model 60 Model 60A Model 67 Model 68 Model 69 Model 70 Model 72 Model 75 Model 121 Model 131 Model 141 Model 320 Model 325 Model 670 Model 770 Pump-action Model 1890 Model 1906 Model 61 Model 62 Model 62A Model 270 Semi-automatic Model 1903 Model 1905 Model 1907 Model 1910 Model 30 Model 63 Model 74 Model 77 Model 100 Model 190 Model 490 Full-automatic Olin/Winchester FAL Model 1917 Falling-block action Model 1885 Shotguns Pump-action Model 1893 Model 1897 Model 1912 Model 25 Model 42 Model 1200 Model 1300 Lever-action Model 1887 Model 1901 Model 9410 Single-shot Model 20 Model 36 Model 37 Model 37A Model 41 Double-barrel Model 21 Model 24 Model 96 Model 101 Semi-automatic Model 1911 SL Model 40 Model 50 Model 59 Model 1400 Model 1500 SX-1 Cartridges .17 Winchester Super Magnum .22 Magnum (WMR) .218 Bee .219 Zipper .22 Hornet .220 Swift .223 Winchester Super Short Magnum .225 Winchester .243 Winchester .243 Winchester Super Short Magnum .25-20 WCF .25-20 Winchester .256 Winchester Magnum .25-35 Winchester .25 Winchester Super Short Magnum .264 Winchester Magnum .270 Winchester .270 Winchester Short Magnum 7mm Winchester Short Magnum .284 Winchester .30-30 Winchester .307 Winchester .308 Winchester .300 Winchester Short Magnum .300 Winchester Magnum .32 Winchester Special .32-20 Winchester .325 Winchester Short Magnum .33 Winchester .338 Winchester Magnum .345 Winchester Self-Loading .348 Winchester .35 Winchester .35 Winchester Self-Loading .351 Winchester Self-Loading .356 Winchester .358 Winchester .375 Winchester .38-40 Winchester .38-55 Winchester .38-56 WCF .38-72 Winchester .40-60 Winchester .40-72 Winchester .401 Winchester Self-Loading .405 Winchester .44 Henry .44-40 Winchester .45-60 Winchester .45-75 Winchester .458 Winchester Magnum .50-110 Winchester