North American production of the .303 British, 1914-1918

I considered briefly trying to tack this onto the recent “303 British with J headstamp” thread but rethought that idea. What I would like to know is: who produced the .303 cartridge for the armed forces of the British Empire during World War One in North America? I don’t recall ever having seen a systematic list of these producers in the U.S. and Canada. Jack

And, while the experts enlighten us about that, what kind of ammo did the U.S. military have for use in the 20,000 .303 Ross rifles purchased from Canada?

The List is fairly small,
Remington (RA); Winchester (or Western?) (W); United States cartridge Co. (USCCo); Peters §; Hoboken Brass (H). Any others???
Ammunition produced was .303 Mark VII(z) (US Bullet) and a small Contract of Mark VI by ?Remington? marked also “LE”. Powder used was mostly Dupont #16, with some #16-1/2 also being used.

These two Powders, although being DuPont’s new “Military Rifle” series, had a short shelf life, with most of this ammo (and Powder shipped to Britain) being either dumped at Sea at the end of WW I, or given away to the Baltic States and Portugal.

The French Airforce in 1916-17, remanufactured a lot of USCCo .303 by adding Primer Crimps for Aircraft MG use, and even using the Primed shell cases with British made AP Bullets and French Powder, before producing their own .303 Ammo by 1917.

The US Bullet ( 170-175 grains) did not have the point of fibre or aluminium, and thus was shorter in its OA length, but the OAL of the Cartridge was that of the British Mark VII.

Cases were all Boxer primed, Corrosive (.210 Large Rifle).

As to the ammo used by the Ross Rifles ( as training rifles), either US -made ammo or Canadian-made ammo would have been used. I have no indication either way. Records in either US or Canadian Archives will solve this problem.

Doc AV
AV Ballistics.

Doc: The H headstamp on .303 indicates National Brass and Copper Tube of Hastings on Hudson. Cartridge cases (none in .303?) produced by Remington’s Hoboken, N.J. facility were headstamped RA H. I have seen U.S. .303 cases made during the war by Winchester, USC, and Peters, but I don’t recall any by Remington or Western. As far as Canadian production is concerned I know of that by the original Dominion Arsenal plant and by the facility at Lindsay, Ontario. Was there not also some production by (or for?) the Ross Rifle Co.? Jack

Another related .303 question. After Pancho Villa’s raid on Columbus NM in 1916 and the mounting of Gen. Pershing’s punitive expedition into Mexico, Pershing essentially commandeered a number of .303 Lewis guns being manufactured by Savage in the US (originally intended for Canada) for his expeditionary force. Apparently after Columbus, he was not sold on the merits of the M1909 Benet-Mercier, plus there were not many of them available. What was the source of Pershing’s .303 ammunition? Any special identification markings showing US use rather than export?

Oops, I seem to be making a habit of this.

“H” is not Hoboken, but as Jack says, the National Brass and Copper Tube Co. of Hastings. They had problems with production and the contract was cancelled after only a limited number of rounds had been produced in 1916. A scarce headstamp to find these days.

Headstamps found on British WWI contracts in America are
Mark VI:
W 15
W 16 VI
W AS 15 (American Standard)
L-E 303 (as Doc says, made by Remington)
P 16 VII (Mark VI depite headstamp)

Mark VII:
H 16 VII
P 16 VII
U 15 VII
W 14 VII
W 15
W AS 15

Other years will be found on most manufacturers other than Hastings.

Total output of .303 inch from the US manufacturers was 952 million rounds of which 64 million Mark VI and 862 million Mark VII were accepted, suggesting that about 26 million rounds were rejected at the factories by British inspectors.

Jack - Canadian production took place at Dominion Arsenal, Dominion Arsenal Lindsay, Dominion Cartridge Co. and as you say, the Ross Rifle Co. Their rounds were headstamped “R.R.CO. CAN. 14 VII” and “R.R.CO. 15 VII”.


Tony: Thanks for the information. The first thing that came to mind when I woke up this morning was that I’d omitted Dominion Cartridge Co. from my list. The U 15 VII should be US 15 VII, should it not? Interesting that none of the U.S. production date from later than 1916. Jack


I don’t really know, but perhaps we had to cut off deliveries of ammunition to other countries because of our own entry into the “Great European War” in 1917, and needed full production facilities for the supply of the American troops?

Yor observation is interesting - something I hadn’t thought of even in the brief few years I was collecting .303.

What does the “L-E” on the mark VI stand for?

Falcon - “Lee-Enfield”?

I should have thought of that. Sometimes the most obvious answer is the least obvious.

No, I have “U 15 VII” which I presume to be the Union Metallic Co.

The reason that there are no dates later than 1916 is because the contracts were cancelled, partly because we were becoming self sufficient in .303 production, partly due to cost and partly due to the poor quality of much of the US ammunition.


Tony: Interesting about the U 15. There then is at least one more possible headstamp because I have a round by USC that is marked either US 15 or US 16; it’s not at hand and I’ll have to check my notes to confirm. Thanks again, Jack

Additions to Tony’s list.

Ball Mk VII:

Primed case:
W 16

Canadian headstamps:
Dominion Arsenal, Lindsay:
L A C 19 17 VII
D.A.L. C 18 VII

Dominion Cartridge Co.


Thanks Attu. My list was representative, not exhaustive, of US headstamps. As I said in that post, other years will be found in most of them except the National Brass one.

Winchester produced a tinned proof round with the “W 15” and “W 16” headstamp, presumably for in-house proofing of the Pattern 1914 rifles. Also USCCo. and Winchester produced expedient drill rounds with tinned cases, empty cap chamber and four small holes drilled in the case.

In addition to being supplied to the French, much USCCo. ammunition was converted to blank or drill rounds in the UK.


Would the US.16 shown be one to add to TonyE’s list of US manufactured 303 British 1914-1918? I have included the other 2 shown as they came from same batch & timeframe. HS not clear reads DA 19 16 VII (Dominion Arms)

Add DC14 VII to list.