Tim,
I have replied to mowermans thread about a stamping that I have on one of my guns.
For the answers to your question, you have to go back to 1904/1905, when BSA first started marketing their guns.
The BSA Air rifle was the first mass produced,& volume marketed airgun in the UK. Up until that point BSA had only either worked on Government contract for military guns or/and made Bicycle spares.Airgun production was a totally new concept. All other guns available on the civilian market were hand made/fitted one offs, made by proper craftsmen gun makers.
The BSA air rifle, was such a ground breaking design, and so very far ahead of other airguns around at the time, that they were very valuable and sought after things. BSA sold them through guns shops as you would expect, but also Village shops, Iron Mongers, Hardware Shops, Garages, Bycycle repair shops.
With so much choice around for prospective purchasers, as to where they could buy their next BSA Air rifle, it is not surprising that a few far thinking suppliers marked their guns with names and addresses etc, so that the gun acted as an on going advertisment for the shop in question.
Also I would think the shops got a bit of positive PR from being associated with supplying the very latest mass produced designs of the new mega accurate BSA Airgun.
Most people would have probably tried the guns at shooting clubs initially, as they were approximately a months wages (for a skilled man) to buy, (so I have been told as I wasn't about at the time) so if they then went on to buy one after initial trials, it wouldn't do the shop any harm to leave their details on the gun. In fact that way they were half way there to the next sale so to speak.
Also in the case of personal stamping by owners, you have to understand that BSA underlevers were used and bought for Bell target/ formal target shooting. They were way too expensive for the average man to use tham as a plinking gun. Good bell target shooters were as locally famous as Top flight tennis stars, or snooker professionals are today. There was no customising of guns or personalisation of guns much in those days, however most people altered sights or adjusted trigger pulls etc according to their personal requirements. Therefore one of the only ways of making sure you always knew which BSA was yours was to personally mark them with names or initals etc. In the same way that a darts or snooker player marks his or her arrows or que etc. This is my theory anyway.
Bell target shooting was serious stuff especially up in the midlands, where serious sums of money were often won or lost. Most pubs/ and working mens clubs etc had their own teams.
Most people don't realise that the old BSA's were such hot stuff when they first came out. And in my opinion they still are pretty good 100 years on.
All the best Tim
Lakey