4 Inch DTH BITS

4 Inch DTH Bits in 108–130 mm Diameters

MSD supplies 4 inch DTH bits with MSD4A, DHD340, QL40, MISSION40, and SD4 Bit Shank options. The confirmed product range includes 108, 115, 127, and 130 mm bit diameters.

All listed configurations use a convex-face design. Gauge-button layouts, front-button layouts, button shapes, spline counts, and weights vary by diameter and Bit Shank. The complete configuration should therefore be checked rather than selecting the bit by its nominal 4 inch classification alone.

Available Bit Shanks

The confirmed 4 inch DTH bit range includes five Bit Shank options: MSD4A, DHD340, QL40, MISSION40, and SD4.

Each Bit Shank group is currently listed in 108, 115, 127, and 130 mm diameters.

The required Bit Shank must be confirmed against the exact DTH hammer model or existing drilling system. A similar nominal hammer or bit size does not confirm that different shank systems are interchangeable.

Bit Diameter and Button Layout Options

The current product range contains two main button-layout groups.

108 and 115 mm configurations — Use 7 × Ø16 mm gauge buttons and 6 × Ø14 mm front buttons.

127 and 130 mm configurations — Use 8 × Ø16 mm gauge buttons and 4 × Ø14 mm plus 3 × Ø13 mm front buttons.

These values describe the confirmed configurations in the current product table. The larger diameters do not simply use scaled versions of the smaller bits, because the number and arrangement of the gauge and front buttons also change.

Face Design, Button Shape, and Spline Differences

All five listed Bit Shank groups use a convex-face design, but their button-shape descriptions and spline counts are not identical.

MSD4A, DHD340, MISSION40, and SD4 — Listed with Spherical + Ballistic buttons.

QL40 — Listed with Domed + Ballistic buttons.

MSD4A — 8 splines.

DHD340 — 8 splines.

QL40 — 10 splines.

MISSION40 — 12 splines.

SD4 — 8 splines.

The parameter table uses Spherical and Domed as distinct button-shape descriptions.

Matching the Bit With the DTH Hammer

The nominal 4 inch classification is only the first selection step. The DTH bit must use the Bit Shank required by the exact hammer model. The confirmed MSD hammer range pairs MSD4A with the MSD4A shank, DHD340 with DHD340, QL40 with QL40, M40 with MISSION40, and SD4 with SD4.

The confirmed MSD hammer range also includes TD40 with the TD40 shank, but no TD40 bit configuration is listed on this 4 inch DTH bit page.

Bit Shank matching alone does not confirm the complete configuration. The selected bit diameter must also be checked against the confirmed hole range of the exact hammer model. The current 4 inch hammer models are specified for Ø110–135 mm drilling. This is especially important for the listed 108 mm bit configurations, which should not be assumed to match the current hammer range without separate technical confirmation.

For replacement orders, provide the complete hammer model, current bit marking, required Bit Shank, required bit and finished hole diameter, and product photos or drawings before the order is confirmed.

Typical Drilling Applications

These 4 inch DTH bit configurations may be reviewed for mining and blast-hole drilling, quarrying, water-well drilling, construction, and foundation applications where the required diameter and drilling system are suitable. Final selection should be based on the exact hammer model, Bit Shank, confirmed hole range, formation, and operating conditions.

Information to Confirm Before Ordering

To confirm a suitable 4 inch DTH bit, provide the following information:

Required Bit and Finished Hole Diameter — Required bit diameter and finished hole diameter in millimeters.

DTH Hammer Model — Exact hammer model used in the drilling system.

Bit Shank — Required Bit Shank designation.

Current Product Information — Current bit model or marking, where available.

Reference Materials — Photos or drawings of the current bit and shank.

Required Configuration — Face and button configuration, if already known.

Working Conditions — Rock formation, abrasiveness, drilling application, and operating conditions.

Order Requirement — Required quantity.

For replacement orders, information from the existing hammer and bit, together with the confirmed hammer hole range, should take priority over a general inch-size description.

Why Choose MSD

MSD is a China-based manufacturer of rock drilling tools supplying DTH hammers, DTH drill bits, drilling components, and related products.

MSD focuses on reliable quality, correct tool selection, and technical support. The objective is not only to supply a bit with the requested diameter, but also to help confirm the appropriate Bit Shank and configuration for the customer's drilling system, helping reduce mismatch risk, unnecessary downtime, and the overall drilling cost per meter.

Technical content reviewed by MSD Engineering Team. | MSD — 23+ years of rock drilling tools manufacturing expertise | ISO 9001 Certified | Exporting to 40+ countries