Firing Systems And Priming Methods Flashcards
Non electric initiation set components
M60/M81 fuse igniter or equivalent.
M700 time fuse.
M7 nonelectric blasting cap
Nonelectric initiating set construction overview
- Inspect roll, remove 6 inches
- Conduct 3’ test burn
- Determine desired burn time DBT
- Calculate fuse length
- Inspect and crimp blasting cap, attach igniter
- Mark with dtg, name, system description.
Calculating time fuse.
- Conduct 3’ test burn and calculate ABR per foot
- Convert burn time to seconds
- Divide DBT by ABR
- Convert the decimal to inches and 16’s of an inch
Note (conduct second test burn if ABR is outside 35 to 45 seconds)
Electric initiating set components
Power source (cd450 blasting machine)
Firing wire
M6 electric blasting cap
Knots for tying into line or ring main.
Square knot
Girth hitch with and extra turn
Gregory knot
charge priming knots
M1 dynamite - det cord lace TNT - 4 wrap knot M112 - 4-6 wrap uli Several applications - wiseman knot Urban breaching - spiral knot
M700 time fuse comes in ____
50’ coils
M7 non electric blasting cap contains ____
An ignition charge, intermediate charge and a base charge (RDX. PETN, HMX)
Requirements to set off M6 electric blasting cap
1.5 amps and 3 volts but as little as 1/4 amp can initiate.
2 ohms of resistance
Det cord specs
PETN core N.E.W. = 12.8 lbs PETN/1000 feet 54 grains per foot We get 1000’ lengths Re factor 1.66
Used to secure blasting caps into explosives with threaded cap wells.
M1A4 priming adapter
Blasting cap test set
M51
Can reliably fire 70 m6’s
Cd450-4j
Reduces capacity of blasting machine by 10 caps per 1000 feet
Greater resistance
WD1/telegraphic transfer comes wire
Primary and secondary initiation systems should be
At least 6” apart
Nonel
Shock tube
Contains 89.5% HMX and 10.5% aluminum powder
Created to replace electric systems
M152 rams components
M26, m16, m6
Low strength caps
M12 w/ 500’ shock tube and M81
M13 w/ 1,000’ shock tube and M81
Will not set off military explosives but will set off det cord
Boosters
M151 and M152
Secondary only, may be buried underground
Splicing shocktube
Only used as a last resort, tubes are at most 1/4” apart
M151 booster
10ft low strength det cord attached to booster cap
5-7.5 gr/ft of PETN
Takes place of branch line and priming not
Can be used to prep time explosives (secondary explosive)
Do not attach to M60 or M81
Most common shock tube misfire
M81 fails to fire
M26 transmitter
2km LOS
Up to 5km with M6 batter pack
Four unique codes and 3 common codes
Firing wire
Available in 200 and 500 ft rolls
Never use anything but ____ to test continuity of electric blasting caps
M51
Used in place of det cord tie in knots, quick and effective
Red and green devils