The locks are a standard back action which were common from the period of 1840-60,this type of back action lock was associated to George Lovell of the 1830,s.The early ones have a separated sear spring with the later ones the main spring acted upon the sear and the tumbler.Over many years restoration work I have come across a vast number of this type and also the very early type of back action locks.
As for the name B&T Redefern my records to not show this name.There was a family by the name of Redfern who over many decades worked in the Birmingham gun trade the first was Bartholomew, Mathew and William 1798-1803 gun makers , Temple Row Birmingham.
Bartholomew 1807-1839 Gun and Pistol Maker,Whittal St 1807-1823,Mary St 1824-1833,Bread St 1834-39,
Thomas Redfern 1837-1850 Gun and Pistol Maker 57,Bread St 1837-1844, 5, Whittal st 1845-50.
The firm of Redfern later became known as Redfern and Bourne.
Feltwad