.44 inch Winchester
In 1915 the Royal Navy purchased 20,000 Winchester Model 1894 lever action rifles in .44 Winchester calibre (.44-40) for use by armed trawlers and mine sweepers. At about the same time 4,000 Remington Model 14 1/2 pump action rifles in the same calibre were bought for the Royal Naval Air Service.
The bulk of the ammunition for these rifles was purchased from Winchester, but smaller amounts were also bought from Remington-UMC.
Ball Mark I
"Cartridge S.A. Ball .44 inch Mark I" was approved to design CIW 2197 in June 1915 for Naval service and shown in Lists of Changes Paragraph 19506 dated November 1917.
The case was rimmed and slightly bottle necked. There was one neck cannelure and the headstamp of the Winchester made rounds was "WRA Co 44 WCF". (The Sealed Patter has this headsatmp)
The bullet was lead with a flattened nose and two cannelures. It weighed 200 grains.
The propellant was 14.5 grains of smokeless powder.
When the Admiralty ordered this ammunition they specified a jacketed bullet, prompted by fears of complaints that a lead bullet contravened the St.Petersburg and Hague Conventions. Winchester said they could provide lead bulleted ammunition immediately but due to wartime orders it would be nine months before they could supply jacketed ammunition. When it was pointed out to the Admiralty that lead bulleted .455 inch ammunition was in service they accepted lead bullets for the .44 inch Winchester.
1914 dated Winchester packet supplied to the Royal Navy.
Sectioned Sealed Pattern of the .44 inch Winchester cartridge held in the Royal Armouries
Dummy Drill Mark I
"Cartridge S.A. Dummy Drill .44 inch Mark I" was approved to design CIW 2307 in June 1915 for naval service and shown in Lists of Changes Paragraph 19506 dated November 1917.
It was made in the general shape of the ball cartridge and was made of tinplate 0.018 inch thick with the base being lap-jointed and headstamped ".44 DUMMY". From the description this was made by Blanch in the same manner as the .303 inch and .256 inch Arisaka dummies. No specimens are known to survive.
For a description of the Blanch .303 inch dummy see here.