mkrnel, I think you are missing the numbers, not of weapons but of men. We are not taking a few hundred or thousand or 10's of thousands we are talking 100's of thousands and millions of men. I don't have the numbers by year and most certainly not every soldier carried a rifle but the bulk did. So whatever was at hand has to do.
No one has mobilized untrained troops in those numbers since WW II so we just don't have a comparable frame of reference for the issues around arming and outfitting them.
I used these quotes from Wikipedia for manpower during 1941 -
In September 1939, the army had a total of 892,697 officers and men in both the full-time regular army and part-time
Territorial Army. The regular army could muster 224,000 men, who were supported by a reserve of 173,700 men. Of the regular army reservists, only 3,700 men were fully trained and the remainder had been in civilian life for up to 13 years.[SUP]
[10][/SUP] In April 1939, an additional 34,500 men had been conscripted into the regular army and had only completed their basic training on the eve of war.[SUP]
[11][/SUP] The regular army was built around 30 cavalry or armoured regiments and 140 infantry battalions.[SUP]
[12][/SUP] The Territorial Army numbered 438,100, with a reserve of around 20,750 men.[SUP]
[11][/SUP] This force comprised 29 yeomanry regiments (eight of which were still to be fully mechanized), 12 tank and 232 infantry battalions.[SUP]
[12]
[/SUP]
Conscription was introduced in early 1939[SUP]
[13][/SUP] to meet the threat of
Nazi Germany, with the
Military Training Act 1939. The Act required all men aged 20 and 21 to take six months' military training. On the outbreak of war on 3 September 1939, the
National Service (Armed Forces) Act 1939 was rushed through Parliament. This extended the liability to military service to all fit men between 20–23. The age group was increased as the war continued,[SUP]
[14][/SUP] ultimately applying to all fit men between the ages of 18–41.
By the end of 1939, the Army's strength had risen to 1.1 million men, by June 1940 it stood at 1.65 million men,[SUP]
[15][/SUP] and had further increased to 2.2 million men by the following June. The size of the Army peaked in June 1945, at 2.9 million men.[SUP]
[11][/SUP] By the end of the Second World War and the final demobilisations in 1946, over 3.5 million men had served in the British Army.[SUP]
[16][/SUP]