A syringe comprising: a syringe barrel; a delivery conduit; a plunger seal disposed within the syringe barrel; and a plunger rod subassembly affixed to an end of the syringe barrel, the plunger rod subassembly comprising: a housing; a first plunger rod component comprising a first linear gear and at least one protrusion; a second plunger rod component disposed at least partially in the syringe barrel and engaged with the plunger seal, wherein the second plunger rod component comprises a second linear gear; a first rotational gear that is pinned to the housing through its axis of rotation, the first rotational gear comprising a plurality of gear teeth for engaging the first linear gear; a second rotational gear that is pinned to the housing and comprises a second plurality of gear teeth for engaging the second linear gear, wherein at least one of the first rotational gear and the second rotational gear is a portion of a compound gear, and the first rotational gear is coupled to the second rotational gear such that translation of the first plunger rod component causes translation of the second plunger rod component; a retainer for affixing the plunger rod subassembly to the syringe barrel, and a rotational component for engaging the at least one protrusion of the first plunger rod component, wherein the first plunger rod component is configured to axially translate in response to rotation of the rotational component when the rotational component is engaged with the at least one protrusion and the first plunger rod component is configured to axially translate in response to a force having an axial component applied directly to the first plunger rod component after the rotational component has disengaged from the at least one protrusion. a syringe barrel; a delivery conduit; a plunger seal disposed within the syringe barrel; and a plunger rod subassembly affixed to an end of the syringe barrel, the plunger rod subassembly comprising: a housing; a first plunger rod component comprising a first linear gear and at least one protrusion; a second plunger rod component disposed at least partially in the syringe barrel and engaged with the plunger seal, wherein the second plunger rod component comprises a second linear gear; a first rotational gear that is pinned to the housing through its axis of rotation, the first rotational gear comprising a plurality of gear teeth for engaging the first linear gear; a second rotational gear that is pinned to the housing and comprises a second plurality of gear teeth for engaging the second linear gear, wherein at least one of the first rotational gear and the second rotational gear is a portion of a compound gear, and the first rotational gear is coupled to the second rotational gear such that translation of the first plunger rod component causes translation of the second plunger rod component; a retainer for affixing the plunger rod subassembly to the syringe barrel, and a rotational component for engaging the at least one protrusion of the first plunger rod component, wherein the first plunger rod component is configured to axially translate in response to rotation of the rotational component when the rotational component is engaged with the at least one protrusion and the first plunger rod component is configured to axially translate in response to a force having an axial component applied directly to the first plunger rod component after the rotational component has disengaged from the at least one protrusion. a housing; a first plunger rod component comprising a first linear gear and at least one protrusion; a second plunger rod component disposed at least partially in the syringe barrel and engaged with the plunger seal, wherein the second plunger rod component comprises a second linear gear; a first rotational gear that is pinned to the housing through its axis of rotation, the first rotational gear comprising a plurality of gear teeth for engaging the first linear gear; a second rotational gear that is pinned to the housing and comprises a second plurality of gear teeth for engaging the second linear gear, wherein at least one of the first rotational gear and the second rotational gear is a portion of a compound gear, and the first rotational gear is coupled to the second rotational gear such that translation of the first plunger rod component causes translation of the second plunger rod component; a retainer for affixing the plunger rod subassembly to the syringe barrel, and a rotational component for engaging the at least one protrusion of the first plunger rod component, wherein the first plunger rod component is configured to axially translate in response to rotation of the rotational component when the rotational component is engaged with the at least one protrusion and the first plunger rod component is configured to axially translate in response to a force having an axial component applied directly to the first plunger rod component after the rotational component has disengaged from the at least one protrusion.