SO, with this idea, the plunger, catch edge, and spring guide are all contained within one small unit that features a simple design with no "sticky outy bits", which allows it to be moulded, printed, forged or machined on a lathe. it's simple design is theoretically strong, as there is little that could tear away or snap, and the lack of plunger rod also means a lighter weight, increasing plunger acceleration.
the twin o-rings allow for different resistance through use of thicker or thinner o-rings, and also stabilises the plunger. the depth of the spring guide can be machined to the compressed length of the spring used, and spacer washers could be used the put higher compression on springs with a shorter compressed length. the catch edge can be as wide as the inner diameter of the plunger tube and can be designed with different taper.
this is the start of the design rendered, feedback appreciated!