7.5mm x 54mm Rubin experimental


#1

Can anybody add to the very limited knowledge I have regarding this rather unusual Swiss experimental cartridge? Datig refers to two versions, this rimless version being the 7.5mm Rubin M1885 and a similar but rimmed version being the 7.5mm Rubin M1886. Presumably these were forerunners of the Swiss 7.5mm Schmidt-Rubin G.P.90 but I understand they also played a part in the design of the British .303.
I’ve tried to photograph the unusal brass collar which sits in the casemouth and which, in turn, holds the bullet. The round also has a very unusual flush primer although my specimen has unfortunately been struck and misfired.
Were all of these made in Switzerland or were they possibly made in the UK as well during development of the .303?




#2

Actually,according to Hoyem,the rimmed version was the forerunner of the 7,5 mm swiss ordnance while the rimmed one served as base for the 303 British cartridge.In both the ring around the bullet was eliminated and the case was modified to take a bottleneck shape


#3

Here are some cutaways - there are a lot of fakes.

ch-munition.ch/quer_ch/index.htm

Click at “Ordonanzpatronen” and scroll down.

Drawings and more pics could be found here

ch-munition.ch/rubin/index.htm

May be contact the swiss guys for more infos.


#4

Well


#5

Greenwood & Batley became the British licence holders for the Rubin patents (often refered to as Rubini in British documents) and the ammunition they supplied initially came from Switzerland. When the War Office finally decided on a rimmed round on the grounds that it would feed and seat better in machine guns (an opinion soon to be changed) Greenwood & Batley received a contract to manufacture 200,000 of the rimmed Rubin round for the 1888 Lee Metford trials. There were also about 15,000 drill rounds issued with white metal cases but it is unclear whether G & B or RL Woolwich made these. RL did make a small number of the rimmed Rubin rounds headtamped R^L 88, the two “8” figures being at 9 and 3 o’clock. The G & B rounds are unheadstamped.

As a general rule, those with the flush primer are Swiss made at Thun, whilst those with a copper domed primer are British.

Photos below show a Swiss rimless, a G & B made trials round and a .303 Mark I Powder as adopted.

Regards
TonyE