Ejection seat Rail?

This could be from a “V” bomber. It has the four housings for the secondary cartridges (on opposite sides of the main body) to incrementaly increase the upwards acceleration of the seat, to enable it to clear the tail.

The conical housing at the right end of the gun fitted into a housing in the cockpit floor. the other end may have the housing for the initiater cartridge, which was spring operated, and held in the safe position by a tapered sear and a safety pin.

This type of ejection gun probably have two tubes mounted one inside the other, fitted inside the cylindrical body shown in the picture.

This is the main gun for the seat not the drogue gun which is attached to the head box. The four circular areas you can see are where the secondary cartridges are fitted. These are sympathetically fired by the hot gases from the primary cartridge as the gun fires. Inside is a telescopic staged tube which extends to propel the seat up the rail and thereby ejection. Ensure that there are no cartridges fitted by removing the circular caps. You need a special peg spanner to do this. If you get the part number from the gun we should be able to identify which seat it is for.

its difficult what you have there is part of the drogue gun and not the launch rail.

Be carefull as it may have two dam big springs inside.This is also the bit that has
the explosive charge in it to fire the seat.

Sorry cant help more than that except to say it isnt Mk3b or Mk4 (Vampire)