Firing Pins Detailed

Question 1

Free Floating (M4, AK, RPK, SVO, M14, M1 Garand)

Answer 1

Larger mass strikes the firing pin. Pin is longer than its carrier so no spring is needed for forward or rearward movement.

Question 2

Inertia (1911, USP, BHP)

Answer 2

Forward energy is created when the hammer strikes the firing pin. As the pin is driven forward it compresses a spring creating the energy needed to reset the pin.

Question 3

Percussion (M60, M2HB)

Answer 3

Pin is driven forward by a compressed spring and is retracted by the cam action that cocks the weapon

Question 4

Striker (P7)

Answer 4

A firing pin is carried inside the bolt and receives its energy from its own spring when activated by the trigger.
A squeeze cocking system is what compresses the firing pin spring

Question 5

Fixed (Blowback MGs)

Answer 5

It’s own mass provides the energy. A protrusion machined into the face of the bolt/breech punctures the primer when the cartridge is fully chambered.

Question 6

Ways firing pins receive their energy

Answer 6

1. A larger mass strikes them (Free Floating)
2. A spring provides the energy (Inertia, Percussion, Striker)
3. It’s own mass (Fixed)