An injection apparatus includes a hollow body having a first end at which a hollow needle is or can be located. A bung with a rupture seal membrane is located within the hollow body. A piston is also located within the hollow body. The piston, the hollow body and the bung define a volume containing a liquid medicament. The bung is nearer than the piston to the first end of the hollow body. The rupture seal membrane initially isolates the needle from the medicament. The rupture seal membrane is configured to rupture through fluid pressure alone without the rupture seal membrane contacting the needle, thereby allowing the medicament to be expelled through the needle upon movement of the piston causing the provision of pressure to the medicament.