S.A. Ball, .303 Inch RIMLESS?


Another GunBroker auction from the same seller in my “Carcano Clip” query.

gunbroker.com/Auction/ViewIt … =118975282

The auction is for a packet of ten cartridges marked S.A.Ball, .303 Inch RIMLESS dated 4-1-19.

Rimless .303?!
Someone please elucidate!


There was a rimless version of the .303 called the .303 magnum. It was a civilian load which had some acclaim in the 1920s for long range match shooting. I think it was introduced by Jeffries.
It was a bit of a nine day wonder in the British target world and interest appears to have dwindled by the 1930s.
It is mentioned in COTW but if we really need someone better than me to flesh out the history.

If those cartridges are 1919 they are early ecamples


The interesting thing, having looked at it more closely , it is clearly military packaging. The plot thickens ! This looks like a job for TonyE. I am not aware of that style of packaging for military ammo for that period (paper wrapped 10 pack) or of the military having any interest in the rimless .303.


Experiments with military rimless .303 ammunition started in 1917. Various case types were tried and one of them, popularly known as the Lewis Gun Rimless (although technically semi-rimless), is quite common, so was presumably made in large numbers. My own example is stamped RL (with the WD arrow in between) 18 I.


Thanks Tony.
The Lewis Gun cartridge immediately came to mind, but I dismissed it because it is semi-rimmed. It would make a lot of sense if it was referred to as rimless. Now if I only had enough X-ray vision to see through that brown paper wrapper…


No need for X-ray vision!

The .303 Rimless (aka Lewis) is relatively common in the UK in the ball loading, and most packets have Date of Work of January 1919.

The origins were a desire in 1917 by both Land and Air services for an improvement in the performance of the service .303 round. A number of rimless and semi rimmed rounds were designed based on earlier work on the .276" rounds necked up to .303". The most promising was that based on design RL 26436 which gave a velocity of 2750 fps.

There were problems with the bullet setting up whilst still inside the case and causing neck separations. A modified design to RL 29338 was produced in 1920 but by then it had been decided that a completely new rimless design was needed with a 200 grain bullet.

The round was initially loaded with a normal .303 174 grn bullet or the 174 grn armour piercing WI bullet. later the VIIG trace and Buckingham bullets were tried but these are extremely rare.

Early cases were unheadstamped with three fire holes but most are headstamped either R^L 18 I or I R^L 1918.

Picture shows L. to R. two ball rounds with the different headstamps and the AP round. Note the pin stab bullet securement on the AP. Still looking for tracer and incendiary!



What exactly defines “Date of Work”?



Date of Work is defined in Textbook of Small Arms 1929 as the date that the ammunition was submitted for inspection.

By that they mean the date it was proofed, which may or not be the day it was manufactured. As you know, every batch of ammo is both visually inspected and fired for pressure, velocity and accuracy.

Generally, in British service “Lots” of ammunition were 200,000 rounds and ammo was proofed at 3 rounds per thousand. Even if the lot was smaller, the minimum number fired for proof must not be less than 450 rounds.

Once it has passed proof tha packeaging is marked with the Date of Work which is in effect a batch number, consisting of the factory cypher and the date inspected, eg “RL31.1.19”. This is used as the unique identifier to back track in the case of any defects.


By the way, if you do come across a .303 rimless in either tracer or incendiary, my birthday is in February.

Happy new Year