Crosman 1377C american classic question.

[HOMER]

The small over cocking rod spring, sets the trigger and iirc also takes hammer pressure from valve stem. The main hammer spring is aboot 32mm long (?) and is shorter than the gap available (@35MM?), the hammer assy I would guess was factory designed as a sealed unit, however access can be gained by milling /filing the rear of the hammer shaft to release the assembly. This is really only necessary if one or both of the aforementioned springs are in need of replacement as the standard unit is more than adequate for the pressure involved. Reassembly can be secured either by tapping / threading or secure welding of the rear hammer shaft stub at the cocking bolt.
HTH
Good luck