generally yes, I say generally because if a soldier doesn't keep the weapon clean then it's not helpful to introduce it into a water environment.
The SA80 (Small Arms for the 1980s) is a British family of 5.56mm small arms. It is a selective fire, gas-operated weapon. SA80 prototypes were trialled in 1976 and production was completed in 1994.
The L85 rifle variant of the SA80 family has been the standard issue service rifle of the British Armed Forces since 1987, replacing the SLR L1A1 variant of the FN FAL. The improved L85A2 remains in service today. The remainder of the family comprises the L86 Light Support Weapon, the short-barreled L22 carbine and the L98 Cadet rifle.
Thank you for the rep and little info on the weapon in the picture.