First date...and I broke her.....

[Peter Laidler]

Definately a British Fazakerley flash eliminator as KtK says, shortened at the rear, pushed on to an unthreaded barrel and fixed with a grub screw. The forward thrust forces on the flash eliminator are tremendous. And the notion that a grub screw was going to retain it is something that a 5th year schoolboy would realise! When something wants to go, it goes - just like that!

To be really honest, if you thread the muzzle (anyone know the thread off hand?) on the basis that you aren't going to do a lot of bayonet fighting, you could just thread the f/e on tight and lock it with locktite as per the SA80