Oh my! That is a very pretty old girl indeed!
Small Cone (chamber).
Sold Out of Service legally, too.
Yes, the "40" part of "1940" was marked independently.
What BSA did between the Wars was keep the plant tooled up and halfway into mothballs. Every tool was greased or oiled or whatever and tooling was checked periodically to ensure that it still worked properly. That took care of the PLANT.
But the OTHER part of rifle production is the STAFF and BSA had been forced to lay off a lot of men at the end of the Great War. They kept as many as possible at work in the motorcycle plant, especially the critical staff members from the rifle plant but, over a period of 20 years, that work force AGED. Men who were 20 became 40, men who were 30 became 50...... and men who were already 50 became 70..... and were retired, taking their former skills permanently OFF the job market.
To mitigate this circumstance, whenever an employee from a critical part of the plant was due to retire, BSA would start up his part of the rifle plant long enough for him to train several younger men precisely how to do his job. Then that part of the plant was shut down again. This would have been exactly the same for the forging shop, barrel-rolling, rifling, reaming, the woodworking shop.... every part of the rifle factory you could imagine.
Take a VERY close and careful look at an SMLE some time. There are milling cuts in that thing which are damned HARD given the machine tools and the technology of 75 or 100 years ago. One excellent example is the channel for the locking lugs of the bolt. The upper lug (the rib) locks on the outside of the rifle, but the lower lug locks in the LEFT SIDE of the rifle but it TRAVELS in the BOTTOM of the rifle. To mill that channel requires a straight milling tool with a relatively long shaft..... and the whole thing must be a cutting tool.... and perfectly parallel at one and the same time. The Body (receiver) less the Bridge Charger Guide must travel against the stationery milling cutter as the top channel in the Body and the bottom channel in the bolt-way are machined. That's bad enough, but then the Body must be TURNED around an imaginary axis which passes along the centreline of the bore..... which does not exist yet. But it doesn't just TURN through its 80 degrees or whatever, it turns in TWO STEPS while continuing to move against the milling cutter. Only the final bit of the cut is done perpendicular to the (imaginary, so far) bore. THAT cut was one of the most difficult in the entire rifle AND it was utterly CRITICAL that it be done to perfection. Needless to say, BSA was most particular to be sure to have sufficient men available who could do THAT job.
Practices such as these would, as you can see, result in a pile of finished and semi-finished parts littering the plant from one end to the other, each part being moved a bit farther along the line when it came time to train new men to do the next job. As this practice continued for a period of some 20 years, during which thee were only TWO main foreign contracts totalling 32,000 rifles in all..... and NONE for England, it is easy to understand that when the PANNNNIC button was hit right after the SHTF button was mashed into subjection, they just might have some Bodies already finished, more partway along the line, others in the milling shop, some being Shaped, others in Forging and so forth. What history DOES record is that the plant was in FULL operation very nearly immediately after the orders were given. During that period of the War, BSA was not just the centre of British rifle production, it was ALL THERE WAS.
Nabs, it is entirely likely that your rifle's Body was turned out well before the War started, likely in 1938 (second Iraqi delivery), less likely in 1936 (first Iraqi delivery) and turned out to be surplus to the Iraqi contract, so was not dated nor completed into a rifle. When the SHTF button was mashed in 1940, it was ready or almost ready to be built into a rifle, so any finishing work would have been done, the thing punched with the date and then built, very quickly indeed, into a rifle, crated and delivered.
If there are recycled parts on your rifle, they likely would have been installed by the Army. I do not know if used spares were delivered from Enfield stocks to BSA or not, although it would seem practical. On the other hand, have you ever tried to tell anyone what is POSSIBLE.... when they don't want to listen? The Government demanded the impossible from BSA...... and then, somehow, they GOT IT.
And that is the miracle.
And your rifle is a part of it.
Hope this helps.
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