.303 British Service Cartridge
The .303 British Service cartridge, usually refered to as the .303 or .303 British was adopted by Britain in
conjunction with the Lee - Metford Rifle in 1889. This round, when adopted, consisted of a 215 grain, round nosed, cupro
nickel jacketed bullet in front of 71.5 grains of RFG2 Blackpowder. The powder charge being pressed into a pellet with both
ends slightly rounded and pierced with a flash hole through the centre. There was a glazeboard wad placed on top of the charge
to protect the base of the bullet. Initially it had a small boxer type primer, and designated Cartridge, S.A.,
Ball, Magazine Rifle, Mark 1.C. Solid Case, .303inch. It also had a muzzle velocity of 1830 feet per second and
a chamber pressure of about 19 tons per square inch.
The original propellant was Cordite begining in 1891 and the first adopted cordite cartridge, the Cartridge S.A. Ball,
Magazine Rifle Cordite Mark 1, had a 215 grain round nosed cupro-nickel jacketed bullet giving a muzzle velocity of about
1970 feet per second with a chamber pressure of about 17.5 tons per square inch. Cordite consists of 58% Nitro-glycerine,
37% Nitro-cellulose and 5% Mineral Jelly and normally was pressed into cord form but tubular, tape, flaked and sliced
cordite were also used. Nitro-cellulose was first used as a propellant in the .303 cartridge during 1894 although not
officially approved for service until 1916. This propellant, however, was considered to be not as stable as cordite in
the tropics and cordite, therefore, was still retained as a propellant in military cartridges for the remainder of the cartridges
service life. Nitro-cellulose propellant however was used extensively during the first and second world wars. The last
.303 ball cartridges were manufactured at Radway Green in 1973 and loaded with nitro-cellulose powder and not cordite,
cordite having last been used for the .303 cartridge in the 1960s.
Round nose bullets on the Black Powder Mark 1 and 2 and of the Cordite Mark 1 and 2 was felt by many servicemen to
have less man stopping effect than the old lead .45 inch Martini bullet, which proceded .303 cartridge. This was confirmed
by experience that was gained in the Chitral and Tirah expeditions of 1897/98 on the North West Frontier of India where the
round nose ball round compared poorly against the .303 inch Dum Dum rounds specially issued in 1897. The cupro-nickle jacketed
bullet, produced at the Dum Dum ammunition factory in India, had an exposed lead nose which gave it a rapid expansion
on impact and greater wounding effect when it hit a body. Following experimentation to increase the effectiveness of
the ball cartridge the British Government adopted a 215 grain cupro-nickle jacketed hollow pointed bullet in 1897 as the Cartridge
S.A. Ball .303 inch Cordite Mark III. Similar jacketed hollow point bullets were used in the Mark IV and V rounds. The soft
nosed and hollow pointed bullets were considered however to be in contravention of the St Petersburg Declaration and the Hague
Convention, being considered in humane. Much like the modern rule of flamethrowers being used against personel. In 1903
they were withdrawn from active service and were afterwards to be used solely for target practice. The Mark VI round was introduced
in 1904 with a 215 grain jacketed round nosed bullet similar to the Mark II bullet but with a thinner jacket.
In 1910 the 174 grain pointed Mark VII bullet was adopted and the muzzle velocity was increased to 2440 feet per second.
This mark of bullet remained the standard ball round for the remainder of the .303 cartridges service life.
the .303 Mark VIIIZ round was approved for the Vickers Machine Gun in order to obtain greater effective range. This round
had a nitro-cellulose powder charge with a 175 grain boat tailed, streamline, jacketed bullet having a muzzle velocity of
2550 feet per second. Chamber pressure however was higher at 20 - 21 tons per square inch compared to the 19.5 tons per square
inch of the Mark VII round.
Tracer, armour piercing and incendiary cartridges were adopted by the British Government during 1915, with explosive bullets
having been approved for service in 1916. These rounds were developed over the years and saw several Mark numbers. The
last tracer round introduced into British service was the G Mark 8 round approved in 1945, the last armour piercing round
was the W Mark 1Z introduced in 1945 and the last incendiary round was the B Mark 7 introduced in 1942. Explosive bullets
were not produced in the UK after about 1933 due to the relatively small amount of explosive that could be contained in the
bullet which limited their effectiveness. Their role could be successfully fulfilled by the use of Mark 6 and 7 incendiary
bullets which were also of a less complicated construction.
In 1935 the .303 O Mark 1 Observing round was introduced for use in machine guns. This type of round was designed to break
up with a puff of smoke on impact with a target or the ground . It was designed as a training aid only, for the observation
of long range shooting where accuracy of fire was not always easily defined, even if tracer ammunition was used. The later
Mark 6 and 7 incendiary rounds could also be used in this role if required.
Since its introduction in 1889 the .303 cartridge t has been manufactured in at least 20 countries
and in nearly 200 military variants as well as in numerous experimental and sporting cartridge configurations. It may be of
some interest to learn that during the First World War more than 7,000 million Mk 7 ball cartridges were produced by British
The following pages attempt to identify the manufacturers of the .303 cartridge and whilst it is acknowledged that this
may not a complete listing I hope it will give some insight into this historically important cartridge. Should the reader
be aware of any omissions in this manufacturer's listing then the author would be very pleased to hear from them.
The head stamp on a British military round contains a wealth of information about it. This includes year of manufacture,
the manufacturer, the type of bullet and the type of propellant in the cartridge. For detailed information on the ballistics
and reloading data for this cartridge please visit www.303british.com