Note.—In punching fuse see that pin enters up to shoulder to insure penetration of cone d.
If fired for percussion-burst, punch at maximum time-setting but do not remove safety-pin i.
Ignition of time-train c is due to punched hole acting as vent for gases from primer-charge r and compressed powder-ring b.
FRANKFORD ARSENAL CENTRIFUGAL FUSES. BASE FUSE "S".
BEFORE ARMING. AFTER ARMING.
Fig. 41.