To ask His Majesty's Government what consideration they have given in Project Troubler and Project Grayburn to the decision by the US Army to standardise their rifles and light machine guns on a common 6.8-millimetre calibre.
A review of performance requirements and technical solutions is ongoing as part of the concept phase for Project GRAYBURN and Project TROUBLER. Interoperability, (including calibre) with other in service weapons, NATO and other international partners will be considered as part of this process.
Answered on 23 Jan 2026