A valve assembly can include a ruptureable member. The ruptureable member may be secured in place by a first support member, a second support member, and one or more removable engaging elements. The valve assembly can be configured such that the ruptureable member can be removed when a single removable engaging element is removed. In another embodiment, a valve assembly can include a plunger having a substantially solid shaft. The valve assembly can also include a ruptureable section attached to the substantially solid shaft. In still another embodiment, a valve assembly can include a plunger including a stem portion and a motion limiter portion, wherein the motion limiter portion is wider than the stem portion. The valve assembly can also include a spring surrounding the stem portion and the motion limiter portion, wherein the motion limiter portion is configured to keep the spring from becoming fully compressed.