What are the differences between the BSA and the Francotte cadets?
No major dimensional differences at all, in fact the parts will usually interchange with no trouble. I've found a few minor tolerance differences between individual parts, such as one would find in any mass-produced item made in various factories in various countries over a 50-year period (1880s-1930s).
The major noticable difference is in the retention pin that holds the lock mechanism in the receiver. The earliest Francottes (1880s) had a solid pin retained by an additional small thumbscrew; later this was changed to a semi-solid pin with a small spring built into the side of it, to help retain it in the rifle. This second variation also used an additional small slotted screw for retention instead of the thumbscrew. The later BSA variations used only a split pin to retain the lockwork, this is the most-commonly-encountered variation and was used on most of the 310s made in the UK. The final variation, used on many commercial rimfire cadets, is a threaded pin with a knurled and/or coin-slotted head. The major visual difference is the presence of the additional retention screw on the left side of the Francottes, absent on the BSAs.
I'm certainly no expert, I hope that The Double D or MartiniBelgian will chime in here and make any corrections and additions necessary. Meanwhile I'll try to get some pics of the various pins and receivers.
Regards, Joe
