The BSA Autorifle was a British self-loading rifle that was produced by Birmingham Small Arms.[1]
History[]
The BSA Thompson was offered a £3000 prize by the British government and was initially seen to have an advantage over the-then standard issue Lee-Enfield SMLE after automatically ejecting a spent cartridge and replacing it with a new round placed in-battery. The gas pressure excited at the moment of firing locks the threads on the bolt, but as pressure decreases the threads are released, a turning movement is actuated by a spiral spring, and the bolt is unscrewed and passes along grooves to the rear, extracting the spent cartridge which comes into contact with the ejector and thrown out. The rear spring forces the bolt forward again, the turning movement actuated again and the screws interlocked: at the same time a new cartridge is placed in-battery.
Gallery[]
References[]
- ↑ THE COMING OF THE AUTOMATIC RIFLE: TYPES OF NEW FIRE-ARMS. The Illustrated London News, August 11. 1928