In researching surviving papers from the London Small Arms Co. recently I came across the following for Sht L.E. barrels -
order received from MM [Ministry of Munitions] for 1000 ea. Rectangle and [Rectangle-with-a-R-inside]barrels for repair purposes at 12/6d and 9/6d respectively, the prices having been agreed with BSA.
Anyone observed a barrel with these markings? There must have been a reason for the differential in price.