Identification of British .303 inch ammunition can be quite challenging, especially for the beginner. The .303 began life as far back as 1889 and was originally used in the Lee-Metford rifle. Since then it has under gone a number of changes, with a wide variety of bullet types, and is still produced today. It was the main cartridge used by the British army until it was finally replaced in the 1950s by the 7.62×51 Nato cartridge.

The general dimensions of the .303 cartridge are as follows;

Case type	Rimmed, bottleneck
Bullet diameter	7.92 mm (0.312 in)
Neck diameter	8.64 mm (0.340 in)
Shoulder diameter	10.19 mm (0.401 in)
Base diameter	11.68 mm (0.460 in)
Rim diameter	13.72 mm (0.540 in)
Rim thickness	1.63 mm (0.064 in)
Case length	56.44 mm (2.222 in)
Overall length	78.11 mm (3.075 in)

The official nomenclature for the cartridge is the 303 British or 7.7x56R (7.7mm calibre, 56mm case length, rimmed).

The main method of identification to determine the origin and type of 303 cartridge is the headstamp, which will be dealt with later. Other identifying features of the cartridge are the annulus (ring around the primer) colour, bullet tip colour and the colour of the cartridge case itself.

ANNULUS COLOUR

The primer of a cartridge case initiates the main propellent when the firing pin of a weapon impacts against it. There are numerous terms used for the primer, but in British service it is known as the ‘cap’.

A varnish is used to seal the cap in place in the cartridge case, and it wasn’t until the latter stages of WW1 that colour was added to this varnish to help identify different loadings. The ‘ring’ that surrounds the cap is known as the annulus.

COLOUR	LOAD
Purple	Ball and short range practice ball
Red	Tracer (also some explosive rounds)
Green	Armour-piercing and semi armour-piercing
Blue	Incendiary
Black	Explosive and observation
Yellow	Proof and standard
Orange	Some explosive rounds
Clear	Blank

Bullet Tip Colour

As more and more variants were added, it became necessary to identify loadings via as quick a method as possible. The use and variation in colour tips increased greatly during WW2, with coloured tips becoming more and more prevalent as the war progressed

COLOUR	LOAD
White	Tracer G Mark IV and VI (daytime tracer)
Grey	Tracer G Mark V (night-time tracer)
Red	Canadian tracer G Mark II and some British G Mark II
Blue	Incendiary B Mark VII and VIIz
Green	Armour-Piercing W Mark Iz, but only used for export contracts, not British service
Black	Observation Mark I
Orange/Yellow	Believed to be night tracer

Case colour

The 303 comes in a variety of coloured, part-coloured and plated forms.

Black staining to case

The use of a chemical staining method to colour portions, (or the whole), of the cartridge case has been used since 1904, when the Blank Mark VI was introduced. Staining parts or the whole of the cartridge black helps in quick identification of the cartridge type.

Marking	Cartridge
Top half blackened, open neck	Rifle grenade H Mark I
Whole case blackened, open neck	Rifle grenade H Mark II
Top and bottom thirds blackened, rosette crimp	Rifle grenade H Mark 4 & 4z
Bottom half blackened, rosette crimp	Rifle grenade H Mark 7z
Bottom half blackened, open neck	Discharger smoke generator E I.T
Whole case blackened, brass mock bullet	Blank Mark VI (pre 1907)
Whole case blackened, rosette crimp	Blank Mark VI (post 1907)
Top third blackened, bulleted	Short range practice
Bottom third blackened, bulleted	Match ammunition
Top and bottom thirds blackened, bulleted	Match ammunition

Some 303 drill rounds were also blackened.

Marking	Cartridge type
Blackened case and bullet, 4 holes drilled in cartridge case	Dummy drill Mark V (WW1)
Blackened case and bullet, six narrow flutes extending from shoulder	Drill round, produced by Colonial Ammunition Company, New Zealand during WW2
Blackened cartridge case and bullet	Drill round, produced by Winchester repeating Arms USA, supplied on contract in WW2

303 cartridges were also produced with coloured rings around the cartridge case. The colour used can be purple, red, green or black. This was mainly a Canadian manufacturers practice, and usually denoted match ammunition. However, one exception to this was the Canadian tracer G Mark I made by the Dominion Arsenal early in WW2. This had a black band painted around the case, 8mm wide, approximately 10mm above the rim.

The British manufactured 303 cartridges saw two cases with blue bands. The Practice Tracer PG Mark I had a 6mm blue band just above the rim, and the Reduced Charge Ball had a 1 inch blue band around the case. This second cartridge was used to cause a deliberate jam in a Vickers MG to train RFC aircrew in clearing a jam in the air.

Chromed, Silvered or White Metal Cases

A chromed, silvered or white case denoted a Dummy Drill or Inspection cartridge and is usually accompanied by fluting or holes drilled through the cartridge. The fluting was often painted red to highlight it.

Dummy Drill Mark I	Empty brass case, tinned, no cap, coreless bullet
Dummy Drill Mark II	Empty brass case, tinned, no cap, coreless bullet, case coned and indented to secure bullet
Dummy Drill Mark III	Plain (Pre 1907) or red (post 1907) round nosed wooden bullet. Case usually brass but was tinned prior to 1905.
Dummy Drill D Mark VI	Chromed or cupro-nickel case, jacketed spitzer bullet, three vertical flutes, (usually painted red)
Drill D Mark VII & VIIN	Cupro-nickel jacketed bullet with aluminium core, chromed case with three red flutes, empty cap recess sometimes painted red. N denoting naval service
Drill D Mark IX	WW2 expedient. Can be found as plain brass or tinned/chromed cases
Drill D Mark 10	Chromed case with three red flutes. Gilding metal jacketed bullet with empty cap chamber, sometimes painted red
Drill D 1942 Canadian pattern	Chromed case with three flutes
Dummy Inspectors Mark I	Tinned brass case, filled with coal dust, round nosed bullet
Dummy Inspectors Mark II	Tinned brass case, filled with coal dust, round nosed bullet
Dummy Inspectors Mark III	Tinned brass case, filled with coal dust, round nosed bullet
Dummy Inspectors Mark IV	Tinned brass case, filled with coal dust, pointed bullet
Dummy Inspectors U Mark 5 or V	White metal case, blind cap chamber (sometimes painted red), manufactured to normal weight of standard 303 ball

There are other types of finish in 303 cartridges. Polished steel cases were used as armourers tool cartridges and copper washed cartridges were used as proof cartridges.

Headstamps

The headstamp of a cartridge is the major identifier of the manufacturer, year and loading. During the life of the 303 cartridge, it evolved through several steps.

The original 303 Powder Mark I cartridges (manufactured between 1889 and 1890) showed the manufacturers code of RL, (Royal Laboratory, Woolwich),separated by a War Department (broad) arrow at the 12 o’clock position, along with the last two digits of the year of manufacture at the 9 and 3 o’clock positions. There may also be a number at the six o’clock position, showing the case was supplied by a contractor.

The Powder Mark II ball round was manufactured between 1891 and 1893 and showed only the manufacturer and mark number, along with a broad arrow.

In 1891 the Cordite Ball Mark I round was introduced, making it necessary to identify the higher velocity cordite filled rounds. Headstamps included the manufacturer and the letter ‘C’ without a mark number, but this was added very soon after, leading to a headstamp with the manufacturer identifier at 12 o’clock, letter ‘C’ at 7 o’clock and mark number at 5 o’clock. With the production switching entirely to cordite rounds in 1907/8, the ‘C’ was dropped from the headstamp as it became meaningless.

The headstamp also altered the same year to include the year of manufacture, shown as the last two digits of the year at the 2 o’clock position. At the same time, the headstamp of cartridges intended for military use were overstamped with one or two broad arrows. These could appear anywhere on the headstamp and often obliterated other information.

The next change came during WW1 with the appearance of different loadings. These were identified in the headstamp by adding a suffix after the mark number.

Suffix	Load
A.A	Pomeroy incendiary P.S.A. Mark II
B	Buckingham incendiary
F	Kings Norton Semi-Armour Piercing
G	S.P.G. Tracer
K	Brock incendiary
P	Kynoch Armour-Piercing
R.C.	Reduced Charge
R.T.S.	Explosive (Richard Threlfall & Son)
R.T.T.	Explosive (Richard Threlfall Todhunter)
S	Royal Laboratory Armour Piercing
T	S.P.K. ‘Sparklet’ tracer
W	Armour Piercing
Y	Pomeroy Incendiary P.S.A. Mark I

The use of the suffix to the Mark VII headstamp continued until 1926, when an identifier letter and Mark number for each individual load replaced the suffix system. These suffix letters became the new identifier for their specific loads, followed by a mark number for that load. So, for instance, the Armour-Piercing headstamp VIIW became W I (W Mark I). For a very short period at the end of 1926, both the new style coding and previous suffix coding were stamped together, for example VIIGI for tracer Mark I.

Prefix	Load
B	Incendiary
D	Drill
E	Smoke Generator Discharger
F	Semi Armour Piercing
G	Tracer
H	Rifle Grenade
L	Blank
O	Observation
P	Practice
Q	Proof
R	Explosive
U	Inspector’s Dummy
W	Armour Piercing

This system continued until the beginning of 1945, when the Roman numerals were replaced with Arabic numerals, so the VII became 7.

There were two other letters that could appear on a 303 headstamp. The first, the letter ‘Z’ was used to denote the propellant loaded was nitro-cellulose. Interestingly, all 303 cartridges manufactured under contract from the US were loaded with nitro-cellulose, but did not utilise the ‘Z’ code, it was only British manufacturers that did so. The other letter is a ‘T’, used to denote a black powder fill. This was only used in special loads, most notably blanks,

Marking	Propellant
Undated, no code	Black powder
Undated, code ‘C’	Cordite
Dated, no code	Cordite
Dated, code ‘Z’	Nitrocellulose
Dated, code ‘T’	Black powder

The final evolution of the 303 headstamp came in 1954 when the NATO ‘L..A..’ system was adopted. The ‘L’ number showed the type of store and the ‘A’ number reflected the modification level. For instance, the British L2A2 7.62mm ball round had the code L2 identifying it as 7.62mm ball, and the A2 showed it was the second mark.

The Date

Much speculation has surrounded the way the date appears on 303 headstamps, with many believing a 4 digit year code denoted RAF use. This was only partly true, and stemmed from the use of synchronised machine guns used by the RFC in WW1. Due to the need to have precise firing times to allow firing through a propeller, only high quality ammunition giving consistent ignition times could be used. This ammunition was manufactured to the tightest tolerances and identified with a green packaging label. From 1918 onwards the label was switched to red and the cartridges identified by use of a four digit year code. The labels were marked with ‘RAF Special’ or just ‘Special’. In 1939 when WW2 was imminent, it was decided to manufacture all 303s to Air Service tolerances and use the four digit date code. In 1942 a further directive instructed all manufacturers to use only a 2 digit date code from January 1943, and so the four digit code disappeared. It can therefore be said that all 303 ammunition dated 1939 or earlier and using a 4 digit code was for RAF use, but anything after that was for use in any of the services. It is also interesting to note that the RAF only kept cartridges on store for 2 years, after which time any unused cartridges were passed to the army. So just because you find a fired four digit date coded 303 does not necessarily mean it came from an RAF aircraft!

Manufacturer Codes

GREAT BRITAIN

Note that some of the manufacturers in this list had a number of different headstamp codes, utilised at various points during their existence.

Note the War Department Broad Arrow mark, often referred to as the ‘Crow’s Foot’, is shown in graphical form below as .

Code	Manufacturer	Period Used
	Ministry of Supply Factory, Radway Green, Cheshire	1940-41
	Ministry of Supply Factory, Spennymoor, Yorks	1940-42
B	Birmingham Metal and Munitions Co. Ltd	1892-1918
BE	Ministry of Supply Factory, Blackpole, Worcs (cases supplied by RG)	1939-45
B  E	Ministry of Supply Factory, Blackpole, Worcs (cases supplied by K4)	1939-45
BE	Ministry of Supply Factory, Blackpole, Worcs, (cases supplied by own factory)	1939-45
BM	British Munitions Company	1890s
BPD	Bombrini Parodi Delfino	1980s
CP	Crompton Parkinson, Doncaster, Yorks	1939-45
C-P	Crompton Parkinson, Guisley, Yorks	1939-45
E	Eley Brothers	1890s-1918
E  B	Eley Brothers	1889
G	Greenwood & Batley Ltd, Leeds, Yorks	1890-1920
GA	Grenfell & Accles Ltd, Birmingham	1890s
GB	Greenwood & Batley Ltd, Leeds, Yorks	1890s-1958
HN	Ministry of Supply Factory, Hirwaun, South Wales	1939-45
HXP	Greek Powder & Cartridge Company	1980s
J	Birmingham Metals and Munitions Co. Ltd., Waltham, Essex	1914-1918
K	George Kynoch Ltd, Birmingham	1890-1920
K	Kynoch Division of ICI Ltd, Birmingham	1920-76
K2	Kynoch, ICI, Standish, Lancs	1939-45
K4	Kynoch ICI, Yeading, Middlesex	1939-45
K5	Kynoch ICI, Kidderminster, Worcs	1939-45
KN	Kings Norton Metal Co.	1890-1920
L	Lorenz Ammunition Ordnance Co., Millwall, London	1890s
M	Morris Patent Tube Co. Ltd, Birmingham	1890s
M	Nobel Explosives Ltd., Glasgow	1914-18
N	Nobel Explosives Ltd., Glasgow	1914-18
RG	Ministry of Supply Factory (later Royal Ordnance Factory), Radway Green, Cheshire	1942-73
RL	Royal Laboratory, Woolwich	1888-1954
RL.(date).	Royal Laboratory, Cartridge Factory No 3, Woolwich	1917-18
R(Date)L	Royal Laboratory, Cartridge Factory No 5, Woolwich	1915-18
RW	Rudge Whitworth Cycle Co., Nottingham	1939-45
SR	Ministry of Supply Factory,Spennymoor, Yorks	1939-45

India and Pakistan

Production of 303 cartridges commenced in India around 1895, with a characteristic government mark approved for use. This consisted of a capital letter I, above which was the Broad Arrow.

There is a subtle difference between Indian and British headstamps, with the Indian ones carrying the month of manufacture, as well as the year.

Code	Factory	Date
D	Dum Dum Arsenal, Calcutta	1895-1913
DF	Dum Dum Arsenal, Calcutta	1895-1913
K	Kirkee Arsenal	1895-1914
KF	Kirkee Arsenal	1895-1960
N	Dum Dum Arsenal, Northern Circuit	1895-1914
OK	Ordnance Factory, Khamaria, Jubbulpore	1943-1970s
P.O.F.	Pakistan Ordnance Factory	1947 onwards
S	Kirkee Arsenal, Southern Circuit	1895-1913

Canadian

The earliest known date for Canadian 303 production is 1894. The headstamps of Canadian 303s followed the British system, even using the broad arrow initially. However, following incorporation of Canada as a Dominion, the government ownership mark changed to a C incorporating the broad arrow.

During WW2 the Canadians used several variant headstamp arrangements. As an example, from 1943 the Defence Industries used only the manufacturer, year and ‘Z’ nitrocellulose code.

Code	Manufacturer	Period Used
D	Dominion Cartridge Company	1918
DA	Dominion Arsenal, Quebec	Pre 1940 and post 1945
DAC (The C is as above)	Dominion Arsenal, Quebec	1920-45
DAL	Dominion Arsenal, Lindsey	1917-21
DC	Dominion Cartridge Company	1895-1918
DC	Dominion Cartridge Factory (Dominion Arsenal post 1900)	1890s
DCA (The C as above)	Dominion Arsenal, Quebec	1935
DI	Defence Industries Ltd.	1940-45
LAC (The C as above)	Dominion Arsenal, Lindsey	1914-17
RR Co	Ross Rifle Co., Quebec	1915-17

Australia & New Zealand

AF	Small Arms Ammunition Company, Footscray	Jan 1924- Feb 1925
CAC	Colonial Ammunition Company, Footscray	1890-1920
CAC	Colonial Ammunition Company, Auckland	1898-1950s
F	SAAF Footscray	Mar 1925 – April 1926
F	SAAF Footscray	1926
MF	SAAF No 1 Footscray	May 1926-62
MF1	SAAF No 1 Footscray	1940
MF2	SAAF No 2 Footscray	1940
MG	SAAF No 2 Footscray	1940-48
MH	SAAF No 3 Hendon	1940-45
MJ	SAAF No 4 Hendon	1941-44
MQ	SAAF No 5 & 6 Rocklea	1942-43
MS	Salisbury Explosives Factory	1944
MW	SAAF No 7 Welshpool	1942-45
SAAF	SAAF Footscray	1921-23

South Africa

Code	Manufacturer	Date Used
A	Armscor	1975-80
PMP	Pretoria Metal Pressings Pty, Pretoria	1965-75
SAM	South African Mint, Pretoria	1961-65
U	South African Mint, Pretoria	1938-42 and 1945-61
U	South African Mint, Kimberley	1941
U	South African Mint, Kimberley	1942-45

USA

US companies produced millions of rounds of 303 for both World Wars. Virtually all the ammunition produced was standard ball ammunition.

Code	Manufacturer	Date Used
H	National Brass and Copper Tube Co., Hastings, NY	1916
P	Peters Cartridge Co., Kings Mills, Ohio	1915-17
PC	Peters Cartridge Co., Kings Mills, Ohio	1940
RA	Remington Arms Co., Bridgeport, Connecticut	1915-17
U	Remington Arms Co., Bridgeport, Connecticut	1915
US	United States Cartridge Co., Lowell, Massachusetts	1915-17
W	Winchester Repeating Arms Co., New Haven, Connecticut	1914-17
WCC	Western Cartridge Co., East Alton, NY	1940-43
WRA	Winchester Repeating Arms Co., New Haven, Connecticut	1940-43

Inner Case Stamps

During the second world war, companies shipped supplies between each other. Because of this, the loading company and case manufacturer could be completely different factories. As a result, a small identifier was stamped between the fire holes as an ‘identifier’. These stamps are shown below.

Code	Manufacturer
G	Greenwood & Batley
K	ICI Kynoch
R	M.o.S.F. Radway Green
S	M.o.S.F. Spennymoor (the ‘S’ was usually a mirror image)
2	ICI Kynoch, Standish
4	ICI Kynoch, Yeading
5	ICI Kynoch, Kidderminster
	Royal Laboratory, Woolwich

Bullet Base Stamps

Throughout the life of the 303, most bullets for ball ammunition had a makers make stamped into the lead base during the manufacture process.These stamps are shown below;

Code	Manufacturer
	Royal Laboratory, Woolwich (also found with a * or other mark beneath the arrow)
1	Unknown manufacturer (Round nosed bullets)
1	Government Cartridge Factory No 1 (Spitzer bullets)
2	Unknown manufacturer
2	Unknown manufacturer (Round nosed bullets)
3	Government Cartridge Factory No 3 (Spitzer bullets)
6	Unknown manufacturer
B	Birmingham Metal & Munitions Co.
CP	Crompton Parkinson Ltd
D	Dum Dum Arsenal
E	Eley Brothers
G	Greenwood & Batley Ltd
GB	Greenwood & Batley Ltd
K	Kynoch
KN	Kings Norton Metal Co.
O	Royal Laboratory, Woolwich
N	Dum Dum North Circuit (Sometimes mirror image. Round nosed Bullets)
N	Nobel Explosives, Glasgow (Spitzer bullets)
R	M.O.S. Factory Radway Green
RW	Rudge-Whitworth Cycle Co.
S	Dum Dum South Circuit
U	Remington UMC

I do hope that you find all the above useful.

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