Gankai;
I tried to send you a Private Message(PM) but your profile says that you have elected not to receive them. The reason I choose to send you a PM is that your question and subsequent statements lead me to believe that there is information about how British side locks work in regard to the cocking levers and the issues where individuals believe they have strikers (firing pins) issues when they do not. My discussion will be long and most readers here will not likely be interested in the technical discussion. If you want to discuss this send me a PM with your email address.
As to your original question. I suspect you are more interested in when did striker return springs appear in hammerless side lock guns since you are describing receiving such a gun. I have earliest know John Robertson built prototype Boss style SLE which later became the Boss classic design and it was completed on 7Aug1889. It does not have striker return springs and has no room in the action to add them. It works fine without them but the strikers must be made absolutely correct with maximum of .040" protrusion with the tumblers forward and the striker nose completely radiused, hardened and polished for the full length of the protrusion. Since you are having a striker made for you Webley SLE the person making this striker may not be acquainted with precision process of carrying this work out and fitting it to the action for trouble free working.
This Boss prototype early Chilton locks do not even have the built in anvil on the lock plate to limit the forward movement of the tumblers, I suspect your Webley does.
Kind Regards;
Stephen Howell
