Igniter, Time Blasting Fuse: M60, Weatherproof
Overview
The M60 Weatherproof Fuse Igniter is a pull-type mechanical igniter designed to reliably initiate time blasting fuse under all weather conditions, including underwater operations. Representing a significant improvement over earlier friction-type igniters like the M1 and M2, the M60 features a robust metal and plastic construction with a percussion cap firing mechanism that provides dependable ignition regardless of environmental conditions. The M60 served as the primary weatherproof igniter for U.S. military demolition operations for decades and directly influenced the design of its successor, the M81 Igniter.
Country/Bloc of Origin
- Country: United States of America
- Developing Agency: U.S. Army Ordnance Corps / Picatinny Arsenal
- Period of Development: Mid-20th century (standardized by 1960s)
- Arctic Testing: Successfully tested at Fort Churchill, Manitoba, Canada for arctic condition suitability
- International Use: Employed by NATO allies and other nations using U.S. military equipment
Ordnance Class
- Type: Initiating Device / Fuse Igniter
- Primary Role: Initiation of time blasting fuse in all weather conditions
- Delivery Method: Hand-emplaced; integral component of nonelectric firing systems
- Special Capability: Underwater demolition operations (when properly waterproofed)
Ordnance Family/Nomenclature
Official Designations
- Primary Designation: Igniter, Time Blasting Fuse: M60, Weatherproof
- Common Name: Weatherproof Fuse Igniter M60
Related Igniters
- M1 Igniter – Friction-type, non-weatherproof (predecessor)
- M2 Igniter – Weatherproof, percussion-type (concurrent design)
- M81 Igniter – MDI family successor with shock tube capability
Associated Equipment
- M700 Time Blasting Fuse – Primary fuse designed for watertight seal with M60
- Time Blasting Fuse (Safety Fuse) – Also compatible with M60
- Plastic Sealing Compound – Included for waterproofing joints
DODIC
- As assigned for demolition igniter components
Hazards
Primary Hazard Types
- Pyrotechnic: Contains a percussion primer capable of producing flame
- Mechanical: Spring-loaded firing mechanism under tension when armed
Sensitivity Considerations
- Impact: Relatively insensitive when safety pin is in place
- Moisture: Designed to resist moisture; waterproof when properly sealed
- Temperature: Functions reliably in arctic to tropical conditions
Safety Mechanisms
- Safety Pin: Prevents inadvertent firing pin release; attached to pull ring assembly
- Release Pin: Must be deliberately pulled to initiate the firing sequence
Danger Considerations
- Percussion primer produces intense flame upon firing
- Will ignite fuse even underwater if properly waterproofed
- High-pressure gases generated during firing
- Exercise caution when handling after a misfire
Unexploded Ordnance (UXO) Considerations
- A misfired M60 may still contain a viable primer
- The mechanism can be recocked and re-attempted
- If primer fires but fuse does not ignite, follow established misfire procedures
Shipping Classification
- Quantity-Distance Class: 1.4
- Storage Compatibility Group: S
- DOT Classification: Explosive C
- UN Serial Number: 0131
- UN Proper Shipping Name: Lighters, Fuse
Key Identification Features
Physical Dimensions
- Length: 4.8 inches (122 mm)
- Diameter: 1.2 inches (30 mm) at widest point
External Features
- Body Construction: Cylindrical housing (firing mechanism barrel)
- Threaded Cap: Located at one end for firing mechanism access
- Pull Ring: Metal ring with attached safety pin
- Fuse Holder Base: Contains percussion cap and pronged fuse retainer
- Material: Metal and plastic composite construction
Major Assemblies
- Firing Mechanism: Housing containing firing pin, spring, and release components
- Fuse Holder: Pronged retainer that grips the time fuse
- Primer Base: Contains the percussion cap
Color and Markings
- Typically olive drab or natural metal finish
- Lot number and manufacturer markings on packaging
- NSN identification on shipping containers
Distinguishing Characteristics from Other Igniters
- Larger and heavier than M1 or M2 igniters
- Metal/plastic construction versus paper tube (M1)
- Two-piece assembly (barrel and coupling base)
- Threaded connection between major components
Fuzing Mechanisms
Operating Principle
The M60 is a pull-type mechanical igniter utilizing a spring-loaded firing pin and percussion cap primer system. It is specifically designed for weatherproof operation and reliable ignition under adverse conditions.
Major Component Details
Firing Mechanism Assembly:
- Housing with threaded cap on one end
- Firing pin positioned inside housing
- Firing pin spring providing striking force
- Pull rod protruding through top cap
- Release washer for firing pin retention
- Rubber friction seal washer between cap and housing
Fuse Holder Assembly:
- Threaded coupling base
- Pronged fuse retainer (prongs grip fuse, prevent removal)
- Percussion cap primer
Sealing System:
- Rubber friction seal washer at firing mechanism
- Plastic sealing compound (included with igniter) for waterproofing fuse joint
Arming and Firing Sequence
- Preparation:
- Remove protective shipping materials
- Inspect for damage or defects
- Prepare plastic sealing compound if waterproofing required
- Fuse Installation:
- Cut time fuse squarely
- Insert fuse end into pronged fuse holder
- Push fuse in until firmly seated
- Prongs grip fuse and prevent removal
- Waterproofing (if required):
- Apply plastic sealing compound around fuse/igniter joint
- Ensure complete seal for underwater operations
- Firing:
- Pull the release pin/safety pin
- Pull ring action releases the firing pin
- Spring-loaded firing pin strikes percussion cap
- Percussion cap fires, producing flame
- Flame ignites time fuse powder train
Recocking Capability
The M60 mechanism can be recocked if the primer fails to fire:
- Push the pull rod back into the igniter housing
- Listen/feel for click indicating reset
- Pull the release pin again sharply
Waterproof Performance
- Forms watertight seal only with smooth-surfaced M700 Time Blasting Fuse
- Properly waterproofed, will ignite fuse underwater
- Seal integrity depends on proper application of sealing compound
History of Development and Use
Development Background
The M60 was developed to address the significant limitations of earlier fuse igniters, particularly the M1 friction-type igniter. While the M1 was simple and effective under dry conditions, it could not be relied upon in wet weather, rain, or underwater demolition scenarios. Military planners recognized the need for a truly weatherproof igniter that could function in any operational environment.
Design Philosophy
The M60 incorporated several key improvements:
- Percussion Cap Ignition: Replaced friction-dependent ignition with more reliable percussion cap system
- Sealed Construction: Metal and plastic housing with rubber seals protected internal components
- Positive Fuse Retention: Pronged retainer mechanically locked fuse in place
- Arctic Capability: Designed and tested for extreme cold weather operations
Testing and Validation
Environmental testing was conducted at Fort Churchill, Manitoba, Canada to validate arctic performance. Results confirmed the M60 was satisfactory for use under arctic conditions, a critical requirement for Cold War-era operations in northern Europe and other cold weather environments.
Operational Employment
The M60 served as the standard weatherproof igniter for U.S. military demolition operations throughout the Cold War era and into the 1990s. Applications included:
- Combat engineer demolition operations
- Underwater demolition team (UDT) missions
- Bridge and structure demolition
- Minefield clearance operations
- Special operations demolition tasks
Transition to M81
With the introduction of the Modernized Demolition Initiators (MDI) program in 1996, the M81 Igniter began supplementing and eventually replacing the M60 in many applications. The M81’s dual capability to initiate both time fuse and shock tube made it more versatile for the modern battlefield. However, the M60’s fundamental design was so successful that the M81 mechanism is described as “almost identical” to the M60, with the primary difference being the M81’s enhanced shock tube capability.
Current Status
- Legacy Item: Being phased out in favor of M81 for most applications
- Training: Inert M60 igniters remain in use for demolition training
- Stockpiles: Existing stocks may remain in inventory at various installations
- Foreign Military Sales: May still be in service with allied nations
Technical Specifications
| Parameter | Specification |
|---|---|
| Length | 4.8 inches (122 mm) |
| Diameter | 1.2 inches (30 mm) |
| Body Material | Metal and plastic composite |
| Primer Type | Percussion cap primer |
| Actuation Method | Pull-type (spring-loaded firing pin) |
| Fuse Compatibility | M700 Time Blasting Fuse (watertight), standard time fuse |
| Weatherproof Rating | Fully weatherproof; underwater capable |
| Arctic Capability | Validated for arctic operations |
| Filler | Primer mixture |
| Quantity-Distance Class | 1.4 |
| Storage Compatibility Group | S |
Packaging
- 5 per waterproof-wrapped carton
- 60 cartons (300 igniters) per wooden box
- Plastic sealing compound included with each igniter
Frequently Asked Questions
Q: What is the main advantage of the M60 over the M1 friction-type igniter?
A: The M60’s primary advantage is its weatherproof capability. Unlike the M1, which relies on friction-ignited powder that can be degraded by moisture, the M60 uses a sealed percussion cap system that functions reliably in rain, snow, extreme cold, and even underwater when properly waterproofed. This made the M60 suitable for all-weather military operations where the M1 would be unreliable.
Q: Can the M60 be used underwater?
A: Yes, the M60 is designed for underwater demolition operations. However, a watertight seal is only achieved when using the smooth-surfaced M700 Time Blasting Fuse. The joint between the fuse and igniter must be properly sealed with the plastic sealing compound provided with each igniter. When correctly waterproofed, the M60 will reliably ignite the fuse underwater.
Q: How does the M60 retain the time fuse?
A: The M60 incorporates a pronged fuse retainer in its coupling base. When time fuse is inserted, these angled prongs grip the outer covering of the fuse and permit insertion but prevent removal except by force. This positive retention mechanism ensures the fuse cannot accidentally separate from the igniter during operations.
Q: Why was the M60 replaced by the M81?
A: The M60 was designed only for time fuse initiation. When the U.S. military adopted the Modernized Demolition Initiators (MDI) system with its shock tube components, a new igniter was needed that could initiate both traditional time fuse and modern shock tube. The M81 was developed to fill this role, incorporating the proven M60 mechanism with additional features (screw cap, shipping plug system, shock tube reducer) enabling dual compatibility.
Q: What should be done if the M60 fails to fire?
A: The M60 mechanism can be recocked if the primer fails to fire. Push the pull rod firmly back into the igniter housing until you hear or feel a click, then sharply pull the release pin again. If the primer fires but the fuse does not ignite, follow established misfire procedures. In emergency situations where the igniter cannot be made to function, a common match may be used to light the time fuse as a last resort (match-lighting method).
Q: Is the M60 still in military service?
A: The M60 is being phased out in favor of the M81 Igniter as part of the transition to the MDI system. However, existing stockpiles may remain in service at various installations, and inert M60 igniters continue to be used for training purposes. Allied nations who received M60s through foreign military sales programs may also continue to use them.
Q: What environmental conditions was the M60 tested under?
A: The M60 underwent extensive environmental testing, including arctic winter testing at Fort Churchill, Manitoba, Canada. These tests validated the igniter’s performance under extreme cold conditions encountered in northern latitudes. The M60 was determined satisfactory for arctic use, making it suitable for Cold War-era contingency operations in northern Europe and similar environments.
Q: How does the M60 compare in size to the M1 friction igniter?
A: The M60 is substantially larger than the M1. The M60 measures 4.8 inches in length and 1.2 inches in diameter, while the M1 is only about 3.33 inches long and 0.34 inches in diameter. This size difference reflects the M60’s more robust construction with its metal housing, spring mechanism, and percussion cap system compared to the M1’s simple paper tube design.
Safety Notice
All ordnance items should be considered dangerous until verified safe by qualified explosive ordnance disposal (EOD) personnel. Unexploded ordnance should never be handled by untrained individuals. Suspected ordnance should be reported immediately to military authorities or law enforcement. This information is provided for educational purposes and professional identification training only.
Technical Manual References: TM 43-0001-38, TM 9-1375-213-12