Quote Originally Posted by pnird View Post
I have two examples. The first, in .177 calibre, is no.4047 and has the semicircular trigger guard; the second, in .22 calibre, is no. 5017 and has the recurved trigger guard.
Very interesting post, this.

John
That is a surprisingly high serial number for the semicircular trigger guard, but it fits in with another reported example with the same type trigger guard which has the even higher number 4549. Currently the lowest known serial number with the second version trigger guard is 2065, so I think we can conclude that there was quite a long period of overlap between phasing out the large semicircular guard and introducing the neater recurved type, an overlap covering around 1500 production models.