Lancer Tactical LT Viking 13" MLOCK
Lancer Tactical Viking 13" MLOCK Proline Full Steel M4 Airsoft Rifle Instruction Manual
Model: LT Viking 13" MLOCK
1. Introduction
This manual provides essential information for the safe and effective operation, maintenance, and troubleshooting of your Lancer Tactical Viking 13" MLOCK Proline Full Steel M4 Airsoft Rifle. Please read this manual thoroughly before using your airsoft rifle to ensure proper handling and to maximize its performance and longevity.
The Lancer Tactical Viking 13" MLOCK Proline Full Steel M4 Airsoft Rifle is an electric automatic airsoft rifle featuring full metal receivers, handguard, and outer barrel, combined with a polymer stock and motor grip. It is equipped with a Lancer Electric Trigger Unit (ETU) with a fire cutoff system for optimized performance and a responsive trigger. The rifle utilizes a reinforced metal Version 2 gearbox with 8mm bearings, 18:1 steel gears, and a 25k neodymium high-speed motor.

Figure 1.1: Lancer Tactical Viking 13" MLOCK Proline Full Steel M4 Airsoft Rifle (Camo variant).
2. Safety Information
WARNING: Airsoft rifles are not toys. Misuse or careless use may result in serious injury or death. Always wear eye protection. Always treat the airsoft rifle as if it were loaded. Keep your finger off the trigger until ready to fire. Always point the airsoft rifle in a safe direction.
- Always wear ANSI Z87.1 rated eye protection specifically designed for airsoft when handling or operating the airsoft rifle.
- Never point the airsoft rifle at anything you do not intend to shoot.
- Keep your finger off the trigger and outside the trigger guard until your sights are on target and you are ready to fire.
- Always engage the safety mechanism when the airsoft rifle is not in use or when handling it.
- Ensure your target and its surroundings are clear before firing. Be aware of potential ricochets.
- Use only high-quality 6mm airsoft BBs. Using poor quality or incorrect size BBs can damage the airsoft rifle.
- Never look directly into the barrel.
- Store the airsoft rifle unloaded, with the battery disconnected, and in a secure location away from children and unauthorized users.
- Do not modify the airsoft rifle. Unauthorized modifications can compromise safety and performance.
- Always transport the airsoft rifle in a case, unloaded, and with the battery disconnected.
3. Components and Parts Overview
Your Lancer Tactical Viking airsoft rifle comes with several key components. Understanding these parts is crucial for proper operation and maintenance.
- Receiver (Upper & Lower): Full metal construction, housing the internal components.
- Handguard: 13" MLOCK rail system for accessory attachment.
- Outer Barrel: Metal construction, with an orange tip for safety compliance.
- Adjustable Crane Stock: Polymer stock that can be extended or retracted for user comfort and battery storage.
- Motor Grip: Polymer grip with textured panels for enhanced handling.
- Magazine: 140-round mid-capacity magazine.
- Gearbox: Reinforced Version 2 full metal gearbox with integrated Lancer Electric Trigger Unit (ETU) and MOSFET.
- Hop-Up Unit: Rotary style, adjustable for BB trajectory.
- Flash Hider: Aggressive style, included in the box.

Figure 3.1: Close-up view of the receiver, showing the hop-up adjustment window (red dial visible).

Figure 3.2: Internal components of the Lancer Tactical Gen2 ETU Gearbox.
4. Setup
4.1. Battery Installation
The Lancer Tactical Viking M4 requires a 7.4v Small Stick Lipo battery (not included). The battery compartment is located in the adjustable crane stock, wired via a Small Tamiya connector.
- Ensure the airsoft rifle is on SAFE mode.
- Retract the adjustable stock fully.
- Locate the small lever or tab on the underside of the stock's butt plate. Press or pull this to remove the butt plate.
- Carefully slide the butt plate off to reveal the battery compartment and wiring.
- Connect your 7.4v Small Stick Lipo battery to the Small Tamiya connector. Ensure the polarity is correct.
- Carefully tuck the battery and wires into the stock tube, ensuring no wires are pinched.
- Reattach the butt plate, ensuring it clicks securely into place.
4.2. Loading the Magazine
The rifle comes with a 140-round mid-capacity magazine. Mid-cap magazines do not require winding but need BBs to be pushed in.
- Use a speedloader (recommended, not included) to load 6mm airsoft BBs into the magazine. Insert the speedloader nozzle into the magazine's feed port and push the plunger to load BBs.
- Alternatively, BBs can be pushed in one-by-one through the feed port, though this is slower.
- Do not overfill the magazine, as this can damage the internal spring.

Figure 4.1: Magazine inserted into the rifle.
4.3. Inserting the Magazine
- Ensure the airsoft rifle is on SAFE mode.
- Align the loaded magazine with the magazine well on the lower receiver.
- Insert the magazine firmly until you hear a click, indicating it is securely locked in place. Give a gentle tug to ensure it is seated.
5. Operating Instructions
5.1. Firing Modes
The Lancer Tactical Viking M4 features a selector switch with three positions:
- SAFE: Prevents the rifle from firing. Always engage SAFE when not actively shooting.
- SEMI-AUTOMATIC: Fires one BB per trigger pull.
- FULL-AUTOMATIC: Fires continuously as long as the trigger is held down.
To change firing modes, rotate the selector switch to the desired position.
5.2. Adjusting Hop-Up
The adjustable rotary hop-up unit allows you to fine-tune the backspin on the BB, affecting its trajectory and range. Proper hop-up adjustment ensures straight and consistent shots.
- Pull back the charging handle to open the dust cover and expose the hop-up unit.
- Locate the rotary dial on the hop-up unit.
- To increase hop-up (more backspin, BB flies higher), turn the dial in one direction (usually clockwise).
- To decrease hop-up (less backspin, BB flies lower), turn the dial in the opposite direction (usually counter-clockwise).
- Fire a few test shots to observe the BB trajectory. Adjust incrementally until the BB flies straight for the desired distance before dropping.
- Once adjusted, release the charging handle to close the dust cover.

Figure 5.1: Hop-up unit visible through the ejection port.
5.3. Quick Change Spring System
The rifle features a quick change spring system, allowing for fast and easy spring changes to adjust muzzle velocity (FPS) for different field limits or play styles. This typically involves accessing the spring guide from the rear of the gearbox without fully disassembling the gearbox.
Note: Spring changes should only be performed by experienced users or qualified technicians. Refer to advanced guides or professional assistance for detailed instructions on spring replacement.
6. Maintenance
Regular maintenance ensures the longevity and optimal performance of your airsoft rifle.
- Barrel Cleaning: Use the included cleaning rod with a small piece of cloth or paper towel. Gently push it through the barrel from the hop-up end to the muzzle. Do not use harsh chemicals.
- Lubrication: Apply a small amount of silicone oil to moving parts such as the magazine release, selector switch, and charging handle mechanism. Do NOT use petroleum-based lubricants, as they can damage plastic and rubber components.
- Battery Care: Always use a charger specifically designed for Lipo batteries. Do not overcharge or over-discharge Lipo batteries. Disconnect the battery from the rifle when not in use and store it in a fire-safe bag.
- Storage: Store the airsoft rifle in a cool, dry place, away from direct sunlight and extreme temperatures. Ensure the rifle is unloaded and the battery is disconnected before storage.
- Gearbox Maintenance: Internal gearbox maintenance (e.g., re-greasing gears, checking piston/cylinder seals) should only be performed by experienced technicians.
7. Troubleshooting
This section addresses common issues you might encounter with your airsoft rifle.
| Problem | Possible Cause | Solution |
|---|---|---|
| Rifle not firing / No response | Battery not connected, discharged, or faulty; Fuse blown; Motor connection issue; Selector on SAFE. | Ensure battery is connected and charged. Check fuse (if accessible). Ensure selector is on SEMI or AUTO. If problem persists, consult a technician. |
| BBs not feeding / Dry firing | Magazine empty; Magazine not seated correctly; BBs stuck in hop-up/barrel; Faulty magazine. | Load magazine with BBs. Re-insert magazine firmly. Clean barrel and hop-up. Try a different magazine. |
| Inconsistent FPS / Low power | Low battery; Hop-up misadjusted; Air seal issues (e.g., nozzle, cylinder head); Worn spring. | Charge battery fully. Adjust hop-up. For air seal or spring issues, professional service is recommended. |
| BBs curving up/down/left/right | Hop-up misadjusted; Dirty barrel; Low quality BBs. | Adjust hop-up incrementally. Clean the inner barrel. Use high-quality, polished 6mm BBs. |
8. Specifications
Detailed technical specifications for the Lancer Tactical Viking 13" MLOCK Proline Full Steel M4 Airsoft Rifle.
| Feature | Detail |
|---|---|
| Brand | Lancer Tactical |
| Operation | Electric Automatic |
| Construction Material | Metal Upper & Lower Receivers, Handguard, Outer Barrel / Polymer Stock, Motor Grip |
| Firing Modes | Semi-Automatic, Full-Automatic, Safe |
| Muzzle Velocity | 370 - 390 FPS with 0.20g BBs |
| Gearbox | Full Metal Version 2, Lancer Electric Trigger Unit (ETU) with MOSFET |
| Bearings | 8mm Ultra Smooth Bearings |
| Gears | 18:1 Steel Gears |
| Piston | Steel Teeth Polycarbonate Piston |
| Motor | 25k Neodymium High Speed Motor |
| Battery Recommendation | 7.4v Small Stick Lipo (not included) |
| Battery Connector | Rear Wired Via Small Tamiya |
| Magazine Capacity | 140 Rounds (Mid-Cap) |
| Hop-Up | Yes, Adjustable (Rotary Style) |
| Rifle Length | 30.75 - 34 inches (Stock Retracted / Extended) |
| Rifle Weight | 4.6 lbs (approx. 2.09 kg) |
| Caliber | 6mm Airsoft BBs |
| Included Components | 1x Rifle, 1x Magazine, 1x Cleaning Rod, 1x Bag of Sample BBs, 1x Patch, 1x Flash Hider, 1x Manual |

Figure 8.1: Dimensions and weight of the Lancer Tactical Viking Airsoft Rifle.
9. Warranty and Support
According to product information, there is no explicit warranty description provided for this product. For any issues or support inquiries, please contact the retailer or Lancer Tactical directly through their official channels.
For further assistance or to explore other products, you may visit the official Lancer Tactical store: Lancer Tactical Store on Amazon.
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