Rifles
De Lisle Silent Carbine - Specialist issue, very low number produced.
Enfield Pattern 14 (P14) - Used as a marksman weapon until the No.IV Mk.I(T) was introduced, also issued in large number to the LDV.
M1917 Enfield - Issued to LDV.
Martini-Enfield - Used as a reserve arm by Commonwealth troops from India, New Zealand, etc.
Lee Enfield No.1 Mk.III* - Lee Enfield rifle in service at the beginning of the war, supplemented and replaced by the No.4 Mk.I by mid-war.
Lee Enfield No.4 Mk.1 + No.4 Mk.I(T) - Lee Enfield rifle that replaced the No.I Mk.III* in larger numbers mid-war.
Lee Enfield No.5 Mk.I Jungle Carbine - Introduced in 1944 to replace the longer No.1 Mk.III*, and No.4 Mk.I rifles for when in use in the jungles of the Far East.
M1 Garand - American rifle, used in small quantities by special units.
M1 & M1A1 Carbine - American rifle, used in small quantities by special units.
Submachine Guns
Lanchester - British submachine gun, developed from the German MP28, used by the Royal Navy & Royal Air Force.
Sten - British submachine gun from late 1941/early 1942, to the end of the war.
Thompson - American submachine gun used in large numbers until the Sten gun was introduced.
Machine Guns
Bren light machine gun - Light machine gun through the whole of the war.
Browning Automatic Rifle (BAR) - Issued to British Home Guard
Lewis Gun - In service with some infantry at outbreak of war in small numbers, issued to British Home Guard for the rest of the war.
Vicker Gas Operated (VGO) "Vickers K" - Aircraft machinegun, used in specialist roles on Long Range Desert Group and Special Air Service vehicles in North Africa, as well as a short-lived infantry machine gun with the Commandos.
Vickers Medium Machine Gun - Standard medium machine gun of the British Army since 1912.
Browning M1919 - Mounted on many lend-lease vehicles.
Browning M2 - Mounted on many lend-lease vehicles.
Machine Gun, 7.92 mm BESA and 15 mm BESA - British versions of the Czech ZB53 (Model 37) machine gun used as tank and armoured car armament only.
Vickers-Berthier - Indian Commonwealth troops.
Handguns
Enfield No.2 Mk.1 Revolver
Webley Revolver - many marks in .38 and .455 calibres
Browning FN-Inglis "Pistol No.II Mk.I*"
Colt M1911A1
Webley No.I Mk.I - (Automatic pistol in .455 inch). Issued to the Royal Navy
Welrod - silenced pistol
Smith & Wesson Model 10
Colt New Service
Colt Official Police
Grenades
Grenade, Hand or Rifle, No.36M Mk.I "Mills Bomb"
"Grenade, Rifle No.68 /AT" HEAT (High Explosive Anti-Tank) Rifle Grenade
No.69 Mk.I Bakelite Concussion Hand Grenade
No.76, Special Incendiary Phosphorus Hand Grenade
No.73 Anti-Tank Hand Grenade "Thermos Grenade"
Grenade, Hand, No.74 ST "Sticky Bomb"
No.75 Anti-Tank Hand Grenade "Hawkins Grenade"/"Hawkins Mine"
No.77 White Phosphorus Hand Grenade
Grenade, Hand, No. 82 "Gammon Bomb"
Para 9 45 defender
Other
No.II Mk.II Flamethrower "Lifebuoy"
Lewes bomb - Used by the SAS
Fairbairn-Sykes Fighting Knife
Infantry Anti-Tank Weapons
Blacker Bombard - spigot mortar firing HE round
Rifle, Anti-Tank, .55in, Boys "Boys Anti-Tank Rifle" - Infantry anti-tank weapon (prewar - 1943).
Projector, Infantry, Anti-Tank (PIAT) - Infantry anti-tank weapon (1943 until end of war)
Edit- @Mark That's where I got this massive wall of information from, heh.