.303/.22 Experimental M.G. Trainer

Can anyone identify the following .303 cartridge.
The bullet diameter is like an .22
Is it a common one?
Headstamp R arrow L 27 VII


Could be a .22-303. Elwood Epps here in Canada experimented a lot on the .303 making a .303 Improved (Epps) and I believe some .22-303’s. My father tells me the .22-303 was a common wildcat for a while due to the great number of Enfields available. 303British.com lists Royal Ordnance Factory, Woolwich, London as a RL headstamp, this site lists it as Royal Laboratory same location.

According to Datig, “Cartridges for Collectors”, Vol. III, Page 98, this is a .303/.22 Experimental. NOTE: Even the headstamp noted by Datig is the same as yours.

As the Datig entry says, there were three types of bullet, lead, lead with gas check (yours) and solid aluminium. The aluminium bullet was soon dropped as it punched clean through the steel back plates on army 25 yard ranges and consequently is the rearest of the three.

The other two types are scarce but not rare, and I have never seen any other headstamp than R^L 27 VII.

Apparently the lead/gas check round worked well and was about to be approved, but for some reason was abandoned, perhaps because of the cost of the special Vickers barrels that were obviously required.


Many thanks for the information.