Precision CNC Gun Drills | Deep Hole Drilling Machines
Deep precision hole drilling can be applied to different types of metals such as aluminum, alloy steel, stainless steel, titanium, cast iron, and copper alloys. Gun drilling machines use long, thin cutting tools to create high depth, low diameter holes in metal workpieces. A coolant is supplied via a small hole within the tool and chip removal occurs through a groove on the outside of the tool.
Gun drilling machines are widely utilized in various applications in the mold & die, automotive, medical, and metalworking industries by mold makers, job shops, and parts manufacturers. LPR Global provides complete solutions for deep hole drilling including gun drilling machines, combined gun drilling, and BTA drilling machines, and high precision solid carbide tooling that is made in-house.
LPR’s Gun Drilling Machine Advantages
Deep Hole Drilling Applications | Axles, Mold Bases, Heat Exchanger Tube Sheets
Die Cast Mold (DAC-P Steel)
Drill Diameter: 11.02 mm
Cutting Speed: 30 m/min
Feed: 0.028 mm/rev
Coolant Pressure: 50 kgf/cm2
Coolant Type: Oil
Forged Rack Bar (S45C Steel)
Drill Diameter: 12.02 mm
Cutting Speed: 60 m/min
Feed: 0.064 mm/rev
Coolant Pressure: 60 kgf/cm2
Coolant Type: Oil
Input Shaft (S45C Steel)
Drill Diameter: 8.00 mm
Cutting Speed: 80 m/min
Feed: 0.024 mm/rev
Coolant Pressure: 80 kgf/cm2
Coolant Type: Water-soluble
Learn more about LPR Global’s PU Vacuum Foaming Molds.
Gun Drilling & BTA Drilling Machines | Specifications 
Our product line features column-type, knee-type, and combined gun + BTA drilling machines, which are ideal for large or heavy workpieces. The BTA drilling process covers a diameter range of 16-65 mm with a maximum drilling depth of 1800 mm.
Since our inception, we have provided standard gun drilling machine models for mold & die, automotive, and heat exchanger applications. Also, we specialize in custom-built gun drilling machines based on our customer’s workpiece, cycle time, and transfer systems.
Features
KHG Series
Column-type gun drilling machine for large workpieces, injection mold water lines, and ejector pinholes. Ideal for processing heat-treated steel. It can be added with an optional spindle for tapping and chamfering.
Drilling Spindles: 1
Drilling Diameter (mm): 3-32
Drilling Depth (mm): 1,500
Spindle Motor Power (kW): 5.5 to 7.5
Z Axis Motor Power (kW): 1.6
Table Max. Load Capacity (kg): 6,000 to 10,000
KEG Series
Knee-type gun drilling machine with dual manual and automatic modes for multi-hole drilling (water, heat and ejector pinholes) in plastic molds, metal molds, hydraulic manifolds, and heat exchangers.
Drilling Spindles: 1-2
Drilling Diameter (mm): 3-32
Drilling Depth (mm): 600 to 1,000
Spindle Motor Power (kW): 5.5 to 7.5
Z Axis Motor Power (kW): 1.6
Table Max. Load Capacity (kg): 1,000 to 2,000
KEXG Series
Compact, high precision gun drill for mass production of small & medium-sized parts, small diameter holes, and mold sleeve pinholes.
Drilling Spindles: 1-2
Drilling Diameter (mm): 2-12
Drilling Depth (mm): 400 to 800
Spindle Motor Power (kW): 1.5 to 7.5
Z Axis Motor Power (kW): 1.6
Table Max. Load Capacity (kg): 1,000
KHBG Series
Combined Gun + BTA Drilling machine for fast and precise machining of various workpieces and materials. Applicable to small to large industrial, hydraulic and heat exchanger parts. An optional angle plate is available for heat exchanger tube sheet drilling.
Drilling Spindles: 1
Drilling Diameter (mm): GD 7-20, BTA 16-65
Drilling Depth (mm): GD 1,500, BTA 2,100
Spindle Motor Power (kW): 22 to 26
Z Axis Motor Power (kW): 7.0
Table Max. Load Capacity (kg): 6,000 to 10,000
KHBG-W Series
Combined Gun + BTA Drilling machine with a large worktable for heavy workpieces up to 25 tons. Applicable to large or heavy industrial, hydraulic, and heat exchanger parts. An optional angle plate is available for heat exchanger tube sheet drilling.
Drilling Spindles: 1
Drilling Diameter (mm): GD 7-20, BTA 16-65
Drilling Depth (mm): GD 1,500, BTA 2,100
Spindle Motor Power (kW): 22 to 26
Z Axis Motor Power (kW): 9.0
Table Max. Load Capacity (kg): 25,000
KTBG Series
Combined Gun + BTA Drilling machine for production of cooling channels in heat exchanger tube sheets. Optional angle plate and V-block are available.
Drilling Spindles: 1
Drilling Diameter (mm): 7-32, 16-65
Drilling Depth (mm): 2,150
Spindle Motor Power (kW): 22 to 26
Z Axis Motor Power (kW): 9.0
Table Max. Load Capacity (kg): 35,000 to 50,000
KDG/KIG Series
Compact gun drilling machine for mass production of parts. Capable of 1 to 4 spindles, built-in automatic clamping, loading and parts handling systems, and self-contained structure-type which help maximize floor space.
Drilling Spindles: 1-4
Drilling Diameter (mm): 3-32
Drilling Depth (mm): 400 to 800
Spindle Motor Power (kW): 1.5 to 5.5
Z Axis Motor Power (kW): 1.0-2.1
Table Max. Load Capacity (kg): 1,000 to 2,500
KHRG Series
4-Axis gun drilling machine with moving column, horizontal rotary table, and hydraulic tool holder. Different tools can be attached for tapping, surface milling, and other machining processes. Has applications in precision parts and molds.
Drilling Spindles: 1
Drilling Diameter (mm): 3-32
Drilling Depth (mm): 1,500 to 1,800
Spindle Motor Power (kW): 15 to 18
Z Axis Motor Power (kW): 1.6
Table Max. Load Capacity (kg): 6,000 to 25,000
KWG Series
Specialized gun drilling machine for mass production of automotive camshafts and input shafts, which allows drilling from either side.
Gun Drill Tools and Accessories | Specifications 
All our gun drill tooling is produced in-house and guaranteed to attain high feed rates and high cutting accuracy due to its precision and rigidity. For excellent chip evacuation, we offer single flute and carbide-tipped gun drills with a sharp cutting edge and wide flute ranging from 3 mm to 30 mm. To achieve fast cutting speeds and long tool life, our gun drilling machines are equipped with a low vibrating tool head and reinforced with drill tubes, which reduce eccentricity. A universal tool grinder is complementary for ease in regrinding.
Gun Drilling Process Video
Gun Drilling Technology and Quality Assurance
The roots of our technology can be traced from a joint venture with a leading Japanese firearms manufacturer, Miroku Corporation, in 1986. Over the years, we continue to heavily invest in research and development for the consistent improvement of cutting quality, tool life, and machine accessories. Additionally, we use high-quality European components, including cast iron, drilling spindles, and carbide shanks.
Our manufacturing plant in South Korea conforms to CE, ISO 9001, and ISO 14001 standards. To reduce defects, our semi-automatic tool production line consists of NC machines and follows stringent inspection procedures. Tool straightness is checked 5-6 times in a cycle to ensure high accuracy. To meet 100% reliability, our factory-trained technicians implement a close examination of oil flow. Also, to reduce errors, we utilize ISO-certified isothermal and humidity chambers.
Patents | Gun Drilling Machine Components
Gun Drilling and Deep Hole Drilling
Deep hole drilling machines are metalworking machines that produce holes with high depth-to-diameter ratios. To create extremely straight and precise holes, deep hole drilling machines include self-piloting drills that enable workpiece and tooling rotation. Two common deep hole drilling processes are Gun Drilling and BTA Drilling.
Gun Drilling
VS.
BTA Drilling
- Ideal for small diameter holes (1-50 mm)
- High-pressure coolant enters through a hole in the center of the gun drill
- Chips are discharged through a V-shaped groove on the outer surface of the gun drill
- Ideal for larger diameter holes (20-200 mm)
- High-pressure coolant flows around the outside of the BTA drill
- Chips are discharged through the center of the BTA drill
When to Use Gun Drilling
Gun drilling machines are capable of drilling depths up to 1500 mm. It can also be used to produce shallow holes for applications that need close tolerances for straightness, hole diameter, and surface finishing. The gun drilling process is ideal for standard CNC machines and lathes in certain applications. However, there are restrictions on the drilling depth and accuracy of the results. Dedicated gun drilling and deep hole drilling machines are specially integrated with a counter-rotating mechanism, which reduces hole drift, high-pressure coolant system for chip evacuation, and precision guide bushing, which guides the gun drill into the workpiece. The level of accuracy and superior surface finishing of dedicated gun drilling and deep hole drilling machines are incompatible when gun drilling on standard machine tools.
Gun Drilling Machine Components
A gun drilling machine has key components and can be added with optional features to enhance the hole-making process. It consists of drill guide bushings, whip guides, oil seal rubber gaskets, and bearings, which prevent gun drill vibration and whipping. Other accessories include a filter bypass, oil cooler, automatic coolant retrieval system, high-pressure pumps, clamping jigs, rotational jigs, centrifugal separators, and various types of chip conveyors.