.303 British with headstamp J


Here are two pictures of .303 British cases with manufacturers code “J”. The majority of sources define manufacturers code “J” as Birmingham Metal and Munitions Co Ltd. In the same time, I have not confirmed information that 303 British cases with code “J” where made by formerly F. Joyce & Co, Waltham Abbey, Essex, which became part of Nobel Explosives Co in 1907. Could somebody give me more exact information on this question?

Thanks for any help


Several of the “letter code” Factories in Britain were set up specifically during WW I; These are “M”, “N”, “J”, “RW” and of course the Government Cartridge Factories (GF 1, GF 3…some times marked “CF”); all were run by Commercial Operators (M by BSA, N by Nobels, J ( formerly Joyce, owned by Nobels, and probably run by BSA) RW (Rudge Withworth Cycles) and the Government factories were run by BSA and Kings Norton.
All the “other” letter factories were of pre-war ammunition companies (K Kynoch; G Greenwood and Batley; E Eley; KN Kings Norton; and of course the “R^L” Royal Laboratories, Woolwich Arsenal ( Outskirts of London).
The USA Contract ammo also had letter codes relating to their Factory Names ( RA Remington,W Winchester,P Peters, H Hoboken Brass, etc.)

There are some English language Publications which go into greater details about these WW I factories, especially the manufacturing errors of "M and “N” headstamped cases of 1915 and early 1916, which led to the demise and withdrawal of the Ross Rifles (Canadian) from frontline service because of ammunition jamming during Loading.

Strangely, the (withdrawn) Ross Rifles given to Tsarist Russia in 1916, and also to the Baltic States in 1919-1920s, functioned sufficiently well with Later made( better toleranced) .303 Ammo, that after WW II, the Ross Actions were re-built for the Soviet Olympic Team to fire 6,35x54R in the Running Deer and Running Boar Competitions ( 1948, 1952 and 1956.).

Doc AV
AV Ballistics.


Thank you very much!


Apologies Doc, but once again I find myself challenging some of your answers about British military ammunition production.

To begin with, BSA (Birmingham Small Arms) had nothing to do with the production of ammunition in WWI. The company that operated the plants in question was Birmingham Metals and Munitions Ltd, a wholly owned subsidiary of Nobel Industries Ltd. The old Frederick Joyce factory at Waltham Abbey in Essex had been owned by Nobels since 1907 and operated in conjunction with BMMCo. In WWI production of military .303 ammunition commenced and there was considerable interchange of components between the two plants.
It was BMMCo., not BSA, that operated Government Cartridge Factory 1 at Blackheath in Staffordshire, together with Royal Laboratory (GCF2), Kings Norton (GCF3) at Blackpole and Eley Bros.( GCF4) in London.

With regard to the problems of the Ross rifle, whilst it is certainly true that there were problems with some British ammo (more on that below) the real cause was the way the Ross was made.

When the problems first occurred in France it was found by Lt.Col. Harkom, the technical advisor to the Canadian Standing Small Arms Committee, that Ross chambers were undersized. The British specification for the mouth of the chamber was .462", yet the Canadian specification was .460". This was compounded by two factors. Ross was chambering his rifles to .458" and furthermore the rifles were gauged before assembly and not before. Therefore when the barrels were breeched up any over zealous tightening resulted in the chambers being squeezed even tighter. Since British ammo was being made to a specification of .462" it was trying to fit in a .458" or tighter chamber.

Now for the ammo problems. It was also found that some British ammo, particularly that from Birmingham Metals and Munitions Co., made during the great production expansion of 1914/15 had cases that were too soft. They would be forced into the tight chamber, expand when fired and because of the wrong hardness gradient become completely stuck.

It transpired that the reason the Ross rifles had worked in Canada was that Dominion Arsenal (the Canadian ammunition facility) was only accepting and passing minimum dimension cartridges. Quite how the situation had been allowed to arise whereby Canada was manufacturing rifles and ammunition to different tolerances to the imperial norm is not known.

Harkom instructed that chambers should immediately be manufactured to .462" and from 9th July 1915 these rifles were marked with an “N” on the chamber for “Normal”. As the problem persisted the chamber dimension was increased to .464" on 15th August 1915 and it is these rifles that are marked with an “E” for “Enlarged”.

For rifles already in the field in the UK Harkom had all the chambers of the 2nd Canadian Division reamed to .464" before they sailed to France . These are marked “LC” for “Large Chamber”.

Thus it can be seen that the Ross problems were principally of Ross’s own making and cannot be put down simply to badly made British ammunition. The reason that the rifles worked successfully post war in the hands of the Baltic states and Russia was because the chambers had all been reamed and the faulty bolt stops and too brittle or soft bolt lugs corrected.



Thank you, TonyE, for your comments!