Abstract: Systems, methods, and devices are disclosed for facilitating injection of a medicament using an automatic injection device. The automatic injection device includes a housing defining a confined inner space and having a length extending from a proximal end to a distal end along a longitudinal axis. A helical biasing member, or spring, is disposed in the confined inner space, and the spring has an inner diameter at a middle portion that is greater than an inner diameter at the terminal ends of the spring. A syringe plunger has a second bifurcated end extending into an inner bore of the spring. The bifurcated end includes two flexible arms that are able to flex inwardly and outwardly relative to the longitudinal axis within the inner bore of the spring while maintaining an annular gap between the syringe plunger and the spring.