Lee-Enfield No.4 Mk I

Royal Small Arms Factory · Rifle · Discontinued · 1941

Also known as: Rifle No.4 Mk I, No.4 Lee-Enfield, SMLE No.4

Overview

The Lee-Enfield No.4 Mk I is a British bolt-action rifle that served as the standard infantry weapon for British and Commonwealth forces during World War II and beyond. Officially adopted in 1941, it represented an evolution of the earlier SMLE design with simplified production methods, lighter weight, and improved aperture sights. The rifle features a distinctive cock-on-closing bolt action that allows trained soldiers to achieve rapid rates of fire up to 20-30 aimed rounds per minute. Chambered in .303 British, the No.4 fed from a 10-round detachable box magazine that could be loaded via 5-round stripper clips. Over 4 million No.4 rifles were manufactured during WWII at facilities in Britain, Canada, and the United States under the Lend-Lease program. The rifle remained the standard British service weapon until 1957, and saw extensive combat from WWII through the Korean War. Its reliability, accuracy, and firepower made it one of the most successful military bolt-action rifles ever produced.

Specifications

Weight (empty)4100 g (144.6 oz)
Weight (loaded)4550 g (160.5 oz)
Overall Length1130 mm (44.49")
Barrel Length640 mm (25.20")
Action TypeBolt Action
Firing MechanismStriker Fired
Trigger TypeSingle Stage
Trigger Pull27 N (6.1 lbf)
Magazine Capacity10 rounds
Magazine TypeDetachable Box
Muzzle Velocity744 m/s (2441 fps)
Muzzle Energy3122 J (2303 ft·lbf)
Effective Range503 m (550 yd)
Maximum Range2743 m (3000 yd)
Rate of Fire20 rpm
Barrel RiflingLeft Hand
Rifling Twist254 mm (10.00")
Number of Grooves5
Frame MaterialSteel
Barrel MaterialSteel
Stock MaterialWood
FinishBlued

Calibers

Features

Variants

Service history

Operators

Conflicts

Production

Estimated total produced: 4,000,000 · Production years: 1941-1957

Over 4 million No.4 rifles manufactured during WWII at factories in Britain (Fazakerley, Maltby), Canada (Long Branch, 910,000 units), and the USA (Savage-Stevens, 1.2 million units).

Origin

Country of origin: United Kingdom

Designer: James Paris Lee

Discontinued: 1957

Notes

The No.4 Mk I differed from earlier Lee-Enfield models with a heavier barrel, simplified construction for wartime production, and aperture rear sights rather than open sights. The Mk I* variant introduced in 1942 further simplified the design by eliminating the bolt release catch. The No.4 Mk I (T) sniper variant fitted with a No.32 telescopic sight was one of the finest sniper rifles of WWII. Production occurred at Royal Ordnance Factories (Fazakerley, Maltby), Long Branch Arsenal in Canada (910,000 units), and Savage-Stevens in the USA (1.2 million units). In the 1960s, many were converted to 7.62x51mm NATO and redesignated L8. The Canadian Rangers continued using No.4 rifles until 2018, making it one of the longest-serving military rifles in history. Total Lee-Enfield production of all variants exceeded 17 million rifles between 1895 and 1957.

Background

Trained British soldiers could achieve the legendary 'mad minute' with the Lee-Enfield -- firing 30+ aimed rounds in 60 seconds thanks to the rifle's smooth cock-on-closing bolt and 10-round magazine. The Canadian Rangers continued using the No.4 until 2018, making the Lee-Enfield one of the longest-serving military rifles in history at over 75 years.