Yes. You’d think they would have known that. The MP28 components were screwed on and silver soldered. They didn’t vibrate loose.
I didn’t know you can build a semi-auto in the UK. I thought that was verboten.
Here we can build semi-auto guns as long as they comply with our laws. One of the laws requires a closed-bolt system be used. That creates a challenge with the Lanchester because the sear is quite far back on the receiver. One system that seems to work well is a bi-metal bolt. The front is steel and the rear is aluminum. The firing pin and drive spring are similar to the semi-auto Sterling system in concept. The tang on the firing pin is extended and runs in a channel in the aluminum rear section of the bolt. This allows the firing pin tang to be held by the sear when the bolt is closed. The bolt would be too heavy if it was solid steel. The aluminum section keeps the bolt weight where it needs to be to operate correctly. Another option is to move the sear forward, use a trigger linkage similar to a Saiga and a semi-auto Sten bolt. The trigger pull is then up and back.