Why don't you believe that it is blocked if it is not extruding even when the filament is pushed by hand? Filament type? Too cold hot end? If it is ABS, heat to 250C and try to extrude, few times 5mm. If not still extruding, reverse the filament, snip the end of the filament and feed again. Luckily some metal chip garbage comes out when reversing and re-feeding the filament.
Prusa i3, Ramps 1.4. Catnozzle 0.4mm
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