Certainly a "GUNS" Platoon member who simply, as Peter says was carrying for a gun which was "currently" employed on an SF role, as they would be heavily bogged down with Tripod, sight and ammo etc.

Often whilst "switching" targets you and your number two on standby, (not mounted), had to leg it to an extreme distance to provide covering fire as a Platoon/Company or indeed a Battalion were conducting Pairs, Fire and manouvre, re set up at an oblique angle and carryon laying down fire as the rest of the guns moved up. Works everytime as long as you had a view!!!
The "Beaten Zone" proved highly effective in the Sennybridge type terrain or indeed the Falklands the sister sh--hole of training areas where sheep don't like 7.62 on switch

Those in the know will tell you, the butt is not something you want to lose, they are like rocking horse poo, albeit not a starred item, still jail time if lost.