The Lee-Enfield No. 5 Mk. I "Jungle Carbine"

By David Tong

The Lee-Enfield No. 5 Mk. I Jungle Carbine
Photo by David Tong.

The British Army had adopted the Rifle, No. 4 Mk. 1 in 1939. It was a simplified version of the Short, Magazine, Lee-Enfield rifle that served the Empire so well in the first unpleasantness. It was a further simplification and cut down on both material costs and machine time in its construction, much as the No. 1 Mk. III* had been to the original SMLE of 1907. With its heavier, free-floated, 25.3” barrel and fine sights, it provided sterling service in open country conflicts such as North Africa and parts of Western Europe.

In many ways, parallels can be drawn between the U.S. military’s current wholesale adoption of the M4 Carbine and the British developing a shorter and lighter individual weapon for urban or dense tropical combat conditions in WWII. Rather than developing an intermediate powered arm (the U.S. M1 Carbine that proved unimpressive in stopping power during WWII and Korea), the British took a more direct route and simply downsized the standard service rifle.

Two factories were tasked with the production of the No. 5, the Royal Ordnance Factory Fazakerley, Liverpool and Birmingham Small Arms (BSA-Shirley). Fazakerley built approximately 170,000 of them, while BSA built about 87,000 in the three years of production from March 1944 through December 1947. While the No. 5 was originally meant to be a standard-issue replacement for the No. 4, there were some issues related to its construction techniques, as well as the increased recoil levels.

Rumor has it that it was designed primarily for airborne use, rather than the SE Asian jungles, and indeed the No. 5 saw much use in Holland during the abortive Battle of Arnhem, as well as on the Pacific islands. It did, however, serve quite well during the “Malayan Emergency” of 1948-1960, a post-war conflict with Chinese Communist insurgents over oil and rubber industry revenue important to Britain’s postwar economic recovery efforts, as Malaysia was part of the Commonwealth at the time.

Originally, the prototype modifications were carried out on the No. 4 receiver. These included additional machine cuts to the receiver. These can be seen in the deletion of some of the metal below the rear sight, the bolt guide lug’s camming surface and along the right side below the stock line.

The barrel was reduced by 6.5” to a length of 18.7” and its contour was reduced. Still free-floating, it also had material removed from the exterior, known as the “Knox form,” above the chamber area under the hand guard. These took the shape of one flat and several other concave milled cuts circumferentially.

The fore stock was shortened and narrowed, while the upper hand guard and band were removed. A combination flash hider, bayonet lug and front sight mount with protective ears was secured to the barrel by press fitting and two cross pins, similar to what we did with the M16.

The butt stock was shortened and more rounded in the wrist area. The wrist is much more rounded on top than my No. 4 and it is comfortable to wrap one’s thumb around in a firing grip. However, this grip is not conducive to rapid bolt manipulation. One’s thumb might normally be placed straight behind the bolt handle to be able to cycle the bolt with a firm cheek weld. Probably, this made the carbine a bunch more comfortable to be carried at the ready during patrols. Wood furniture was birch (most common), or the occasional walnut, although the latter had been phased out during early No. 4 production.

A stamped steel and rubber butt was fixed to the stock by two screws at the heel and toe. This rubber pad does not provide recoil abatement, contrary to popular wisdom; it was supposed to be a non-skid surface to better locate the rifle during shooting.


  • Type: Bolt-action carbine
  • Caliber: .303 British, Mark VII 174 grain FMJ
  • Overall Length: 39.5”
  • Barrel Length: 20.5” with flash hider
  • Weight: 7 lbs. 1 oz. with empty magazine
  • Magazine: Sheet steel detachable box, staggered column, 10 rounds
  • Rear Sight: Screw click adjustable ladder type graduated 200-800 yards, with standing battle aperture to 300 yards for coarse or rapid firing.
  • Front Sight: Windage adjustable; dovetail, thin-section flat-topped post.

Evidence suggests BSA-Shirley WWII date manufacture is preferable from a collector’s standpoint, due to half as many produced than ROF Fazakerley. WWII production not as nicely manufactured as post-war. BSA Stock band, left butt socket will show “M47C” markings (indicates BSA), while rear sight and elevation knob and front sight are stamped “B”. Fazakerley will have “F” stampings in the same places. Post war fore-stocks will have metal end caps installed to seal the end grain from moisture. Genuine No. 5 carbines have ONLY four digit serial numbers, with lettered prefixes. Serial numbers tend to be “electro-penciled” onto receiver and butt socket, while rear of bolt handle prefix and serial is stamped.

The 1945 BSA Jungle Carbine examined for this article was a bit rougher in both appearance and function than my later 1954 No. 4 rifle. While action cycling was still pretty smooth compared to most of its erstwhile competition, it lacked that bit of polish compared to other L-E's I’ve handled.The bolt body appears to be a casting, evidenced by mold marks on the drilled bolt knob, as well as some evident fine “pebbling” of the bolt’s cylindrical body itself.

The flash hider/front sight base is also a casting, also showing exterior mold marks, as well as some pebbling within the cone. It adds approximately 2” to the barrel length.

Despite their short stocks, the usual metal butt and lots of drop at comb, a standard Enfield rifle is quite a bit more pleasant to fire than a Springfield ’03, Mauser K98, or Moisin-Nagant 91, at least in my experience. This must be due to both the lower operating pressure and subsequent nominal velocities of the cartridge itself.

All of the major power service cartridges of the time (.303 Br., .30-06, 8x57JS, 7.7x58 Jap, 8mm Lebel, 7.62x54R) were overpowered for the close combat conditions encountered in most circumstances, though this extra power was justified for long range capability, as well as penetration.

Barrier penetration, whether it be buildings, light vehicles or foliage, is something at which the current varmint-class 5.56X45mm NATO, 5.45X39 Russian and 5.8mm Chi-Com rounds do not excel. All lack sufficient momentum and sectional density to get those jobs done, compared to those older, heavier, higher-recoiling rounds. This is apparently due to modern “firepower” tactics requiring automatic capabilities. In addition, the short rifle or carbine is best confined to forest, jungle, urban, or vehicular settings, as it loses long-range effectiveness in more open terrain.

A number of theories have been postulated about the “wandering zero” tendency of some No. 5 carbines. This might be because of wood stocks swelling (due to humidity) and causing barrel harmonic issues, or fore stock bedding issues. The most common theories suggest that the lightened receiver became more “springy” during recoil, or that the light barrel heated unevenly during rapid fire. It might even be a reduction of the usual good British quality control in late-war barrels.

The Enfield has never had a tight chamber design and the thinner barrel overheating in protracted use, shorter sight radius, greater felt recoil levels and even shorter stock compounded this issue, as well as intrinsic issues in the design. I am not familiar with the test protocol that armorers in the U.K. used to determine the wandering zero claims, either.

My shooting impressions of the No. 5 are brief. A good friend of mine has owned one for some 35 years and we both remember it feeling “brutal” as teenagers, though certainly accurate enough to 200 yards or so. The 800 yard sight graduation makes about as much sense as the 800m one on our 14.5” M4 5.56mm carbine, save that the .303 has a lot more remaining punch at that ridiculous range.

Shooting the No. 5 at the local gun club on a typical hot summer day reminded me of some of those memories. After years of shooting elephant rifles, my tolerance for recoil possibly exceeds many others. While I do not think that the No. 5 kicks as hard as a Soviet M44, it does come back some. Average five shot groups with Remington/UMC 174 grain hardball ran about 2.5 Inches at 100 yards. I suspect that the usable range should be kept rather short, say 250 yards maximum, on a man or deer sized target.

Suffice to say that the No. 5 was the shortest officially serving rifle in British history, at about 3-½ years. By the time it debuted, the sun had definitely set on the manually cycled bolt action as a general issue weapon of war. While (debatably) the Enfield may indeed be the best of its breed, its time had past, although some units officially used them as late as 1960.

So, what to do with the No. 5? Is it merely a plinker or wall-hanger? Heavens no! Some of the enjoyment depends upon how tolerant you are of recoil, iron sights and two-stage triggers. Some aren’t and there are a lot of you out there and a lot of other rifles you can buy. However, there are legions of shooters who have enjoyed firing or have shot game with other 19th Century, 20” barreled carbines firing medium pressure, rimmed ammunition at moderate velocities. Witness all the Model 336's, Model 94's and sundry copies sold to this day. Last time I checked, they still put venison on the table as well as ever.

In the proper hunting environment, just as in the military application, a carbine can be a handy thing, provided it disposes of enough power. In addition, a usable piece of history is a good thing in my book. Amazingly, No. 5's are apparently still serving to this day in far-flung regions of the world where the Union Jack once flew.

Back to the Collector's Corner

Back to the Rifle Information page

Back to the Naval and Military History page

Copyright 2012 by David Tong and/or All rights reserved.