.243 Winchester Super Short Magnum

243 WSSM

A comparison of the 243 WSSM with 243 Winchester (second from left) and with 22-250 and 223 Remington (far right).

Type

Rifle

Place of origin

USA

Production history

Designer

Browning / Winchester

Designed

2003

Manufacturer

Winchester

Specifications

Parent case

.300 WSM

Bullet diameter

.243 in (6.2 mm)

Neck diameter

.291 in (7.4 mm)

Shoulder diameter

.544 in (13.8 mm)

Base diameter

.555 in (14.1 mm)

Rim diameter

.535 in (13.6 mm)

Rim thickness

.054 in (1.4 mm)

Case length

1.670 in (42.4 mm)

Overall length

2.36 in (60 mm)

Rifling twist

1-10"

Primer type

Large rifle

Ballistic performance

Bullet weight/type	Velocity	Energy
58 gr (4 g) VMax	4,068 ft/s (1,240 m/s)	2,132 ft·lbf (2,891 J)
70 gr (5 g) BT	3,707 ft/s (1,130 m/s)	2,136 ft·lbf (2,896 J)
80 gr (5 g) BTSP	3,545 ft/s (1,081 m/s)	2,233 ft·lbf (3,028 J)
90 gr (6 g) SFT	3,280 ft/s (1,000 m/s)	2,151 ft·lbf (2,916 J)
100 gr (6 g) BTSP	3,136 ft/s (956 m/s)	2,184 ft·lbf (2,961 J)

Test barrel length: 24"
Source(s): Hodgdon ^[1]

The 243 Winchester Super Short Magnum or 243 WSSM is a rifle cartridge introduced in 2003. It uses a .300 WSM (Winchester Short Magnum) case shortened and necked down to accept a .243in/6mm diameter bullet, and is a high velocity round based on ballistics design philosophies that are intended to produce a high level of efficiency.^[2] The correct name for the cartridge, as listed by the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI), is 243 WSSM, without a decimal point.^[3] Winchester has discontinued the manufacture of 243 WSSM ammunition.

Design

The 243 WSSM is an addition to the Winchester Super Short Magnum (WSSM) family of cartridges, which also include the .223 WSSM and the .25 WSSM, and the idea behind the 243 WSSM was to develop a compact, higher velocity version of the well-established and internationally popular .243 Winchester unveiled by Winchester in 1955. The 243 WSSM was first introduced in 2003.

The 243 WSSM's case is unusually short and fat in profile, contrasting markedly with most other rifle cartridges, and is intended to take advantage of what ballisticians have shown is the more uniform and efficient burning of propellant powder when it is held in a short, fat stack by the cartridge case.^[4]

Performance

In their ballistics tables, Winchester list a very high muzzle velocity of 4,060 ft/s (1,240 m/s) with a 55-grain (3.6 g) projectile for this cartridge.^[5] Based on Hodgdon reloading data typical velocities should range from approximately 4,000 ft/s (1,200 m/s) with a 58-grain (3.8 g) bullet to approximately 3,000 ft/s (910 m/s) with a 100-grain (6.5 g) bullet.^[1] The percentage gain in performance over the older .243 Winchester is around 10% or less.

This cartridge is usually used for small game such as varminting, and used for animals as large as deer.

Advantages

Compared to other factory 6mm sporting cartridges the 243 WSSM is capable of functioning in the AR-15 platform.^[6] Other factory produced 6mm cartridges like the 243 Win. and 6mm Rem. are both too long for the AR-15 and require the AR-10 platform.

The 243 WSSM is 3/8 inch shorter than the 243 Win. giving the 243 WSSM the ability to fit in a super-short action rifle. Thus 243 WSSM rifles can be lighter, have stiffer actions and have faster actions to cycle.^[7]

The 243 WSSM gives generally a 10% increase in velocity over the 243 Win.^[8]

References

Cartridge Dimensions at Steves Pages

External links

243 WSSM – The Long-Awaited 6 mm "Answer"? By Bill Prudden
The 243 WSSM by Chuck Hawks
The Experts Agree The WSSMs are Winners! Browning
The 243 WSSM at Guns & Ammo
Hunting experiences with the 243 WSSM 243WSSM.com

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

This article is issued from Wikipedia - version of the Friday, April 29, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.