In Short

A jackleg drill is one of the most widely used tools in underground hard rock mining. It’s versatile, reliable, and when properly matched to the job, delivers fast penetration rates with minimal downtime. But with multiple models and configurations available, choosing the right jackleg drill requires understanding your specific application.

This guide covers the key factors to consider when selecting a jackleg drill for underground mining operations.

What Is a Jackleg Drill?

A jackleg drill is a pneumatic rock drill mounted on a hinged leg-and-feed mechanism. The leg provides support and feeding pressure, allowing a single operator to drill horizontal, inclined, or slightly upward holes without additional equipment.

The jackleg is the workhorse of drift development, crosscutting, and stoping in underground mines. It’s designed to be carried and set up by hand, making it ideal for narrow vein mining and areas where larger mechanized equipment can’t access. If you need more power for deeper holes, consider a pneumatic drifter mounted on a rig instead.

Key Factors When Choosing a Jackleg Drill

1. Rock Hardness

The hardness of the rock formation is the most important factor in drill selection. Harder rock requires higher impact energy and a more robust drill body.

• Soft to medium rock (up to 150 MPa): Lighter jackleg models work well and offer faster cycle times
• Hard rock (150–250 MPa): Requires a heavier-duty drill with higher piston impact energy
• Very hard or abrasive rock (250+ MPa): Demands the highest-rated models with heavy-duty front heads and premium drill steel

2. Hole Diameter and Depth

Standard jackleg drills typically drill holes from 32mm to 45mm in diameter. Deeper holes require longer drill steels and more powerful drills to maintain penetration rate.

• For holes up to 3m: Most standard jackleg models are suitable
• For holes 3m–5m: Look for models with higher air consumption and heavier rotation mechanisms
• For holes over 5m: Consider a drifter on a rig instead of a jackleg

3. Air Pressure and Volume

Jackleg drills are powered by compressed air. Most operate optimally at 90–100 PSI (6.2–6.9 bar). Check the drill’s rated air consumption (CFM) against your compressor capacity — underpowering a drill significantly reduces penetration rate and increases wear.

4. Water Flushing

Underground drilling requires water flushing to clear cuttings from the hole and suppress dust. Most jackleg drills have an integrated water valve. Check that your water supply pressure and volume matches the drill’s requirements.

5. Weight and Handling

Jackleg drills range from around 25kg to 40kg. In tight underground headings, a lighter drill is easier to maneuver and reduces operator fatigue — but lighter drills may sacrifice impact energy. Match the weight to your working conditions and operator capability.

6. Spare Parts Availability

Underground mining can’t afford long equipment downtime. Before purchasing, confirm that spare parts — particularly front heads, pistons, valves, and drill steel — are available and can be delivered quickly.

Questions to Ask Before Buying

• What is the UCS (Unconfined Compressive Strength) of the target rock?
• What hole diameter and depth does the blast pattern require?
• What is the available air pressure and CFM at the face?
• What is the typical heading width — can the operator maneuver freely?
• What is the nearest spare parts supplier and typical lead time?

MC Tools USA Jackleg Drills

MC Tools USA supplies jackleg drills factory-direct from our India manufacturing facility. All models are backed by a full spare parts program and support from our USA headquarters in Boca Raton, Florida. We supply mining operations across North America, Latin America, Norway, and beyond.

Browse Jackleg Drills | Browse Spare Parts by Tools | Request a Quote