Weapon and optics maintenance: cleaning and prevention

The importance of weapon and optics maintenance

Щоб зброя та оптичні прилади (денні або нічні) працювали ефективно та довговічно, необхідно дотримуватись правил експлуатації та регулярно проводити обслуговування. Ігнорування цих вимог призводить до деградації окремих компонентів або повного виходу пристрою з ладу.

Багато користувачів помилково вважають, що оптика має працювати без втручання — це поширена причина передчасного зносу. Особливо це стосується нічного бачення, де навіть незначне забруднення може суттєво вплинути на якість зображення або спричинити пошкодження електронно-оптичного перетворювача (ЕОП).

Regular cleaning is key to ensuring reliable operation of optical systems.

The main reasons for regular cleaning:

• Prevents dust, moisture, and grease from accumulating on lenses, which reduces light transmission and contrast
• Protection of optical coatings against chemical corrosion and micro-scratches
• Maintaining the tightness of the housing and preventing moisture from penetrating the internal components
• Prevention of mechanical wear of moving parts (e.g., mounts or focusing mechanisms)

Main causes of pollution

Очищення зброї та оптики дозволяє усунути накопичені забруднення, що виникають внаслідок постійного впливу зовнішнього середовища та людського фактора. Розуміння джерел забруднення дозволяє вжити заходів для зменшення їх інтенсивності в майбутньому.

Main reasons:

• Human physiological characteristics. Regardless of how careful the user is, sweat, skin particles, and hair inevitably get onto the surfaces of weapons and optics. They accumulate, causing contamination that can affect the functionality of the devices. The only effective method of combating this is to regularly clean areas that are susceptible to such effects.
• Environmental impact. Weapons and optics are typically used outdoors, where they are exposed to dust, sand, moisture, microscopic insects, and condensation due to temperature fluctuations. These factors cannot be eliminated, so systematic cleaning is necessary to maintain equipment performance.
• Errors during storage and transportation. Even in clean rooms, dust is present and settles on surfaces when stored incorrectly. During transportation, the situation is complicated by vibrations and changes in conditions. The use of vacuum packaging partially solves the problem, but due to its cost and inconvenience, most users prefer regular cleaning.

Cleaning weapons and optics

The processes of cleaning weapons and optics differ significantly, so they should be considered separately. Although there are many cleaning options, the basic procedures described below can be adapted to specific operating conditions.

Step-by-step instructions for cleaning weapons

Before starting work

• Operate only as a legal owner of the weapon and in accordance with the manufacturer's instructions in your jurisdiction.
• Completely unload the weapon: remove the magazine, pull back the bolt, and visually and tactilely inspect the chamber.
• Work with gloves and safety glasses in a well-ventilated area. Keep ammunition away from the work area.

What you will need

• Ramrod with bore guide or broach; brushes (bronze/nylon); cotton or microfiber patches.
• Solvent for carbon deposits/copper (compatible with weapon materials), degreaser, lint-free wipes.
• Toothbrush, cotton swabs, cotton pads.
• Gun oil/lubricant; if available, snap caps for safe testing of the USM.

Step 1. Discharging and disassembly

1. Disconnect the magazine, pull back and lock the bolt, check that the chamber is empty.
2. Perform field disassembly according to the manufacturer's manual. Wear gloves while working — this protects your skin from chemicals and prevents greasy marks on parts.
3. Arrange the parts in the order they were disassembled or take a photo—this will make reassembly easier.

Tip: Place a light-colored napkin underneath—it will show the small pins and springs; place small items in labeled trays.

Step 2. Cleaning the barrel channel

1. Install the ramrod guide to avoid damaging the chamber cone. Work from the chamber to the muzzle.
2. Apply the solvent to a scrub brush or patch and make several complete passes. Allow the product to work for 2–5 minutes according to the instructions.
3. Wipe with dry patches until clean. Repeat the cycle 3–5 times if necessary.
4. Do not break the brush in the barrel and do not pull it back in the opposite direction — only remove it outward.

Please note: for chrome-plated/nitrided barrels, use compatible solvents; do not mix ammonia-containing compounds with petroleum solvents.

Step 3. Cleaning the bolt and mechanisms

The main areas of contamination are the bolt face, firing pins, extractor/ejector, guides, and gas assemblies (depending on the design).

• Apply degreaser, brush, and clean the grooves with cotton swabs.
• Inspect the parts for cracks, burrs, and wear on the edges of the extractor/ejector; it is better to replace weakened springs.
• Clean wooden and polymer parts only with compatible cleaning agents to avoid damaging the coating.

Step 4. Light lubrication

The goal is to form a thin film of oil on friction surfaces. Excess oil attracts dust and can impair the performance of mechanisms.

• A drop of oil on the combat stops of the bolt, guides, contact surfaces of the USM (if permitted by the manual).
• A thin anti-corrosion film inside the barrel channel. Remove it with a dry patch before shooting.
• Do not lubricate the cartridge excessively — this may increase pressure and complicate extraction.

Tip: if you are working with PNV, avoid getting aerosols/oil on the lenses of your glasses or external optics — they are difficult to clean in the field.

Step 5. Collection and safe verification

1. Reassemble the weapon in reverse order. If optics/rails are installed, follow the recommended torque settings for the screws.
2. Check the operation of mechanisms with snap caps: safety, bolt release, extraction/ejection, trigger reset.
3. Dry firing is only permitted if expressly permitted by the manufacturer. In case of malfunction, stop the test, repeat disassembly and diagnostics, or contact a specialist.

Useful techniques and facts

• The ramrod guide significantly reduces the risk of damaging the chamber—a critical area for maintaining accuracy.
• Cleaning frequency. For carbines with high-quality ammunition, light maintenance every 200–400 shots is often sufficient; intensive training and "dirty" powders require more frequent servicing.
• Do not mix chemicals. Combining incompatible products may neutralize their effect or damage the coating.
• Storage. After cleaning, remove fingerprints and apply a thin layer of anti-corrosion agent; use silica gel in a safe.
• The muzzle is a sensitive area for accuracy; do not touch it with a ramrod/ramrod.

Note for NVG users: excess lubricant can easily transfer to the eyepieces/lenses of helmet-mounted systems and monoculars (PVS-14, BNVD). Keep microfiber cloths for optics separate and covered.

When to consult a professional

Складні регулювання УСМ, роботи з газоблоками/стволами, прес-посадки та різьбові з’єднання виконує лише сертифікований зброяр. Якщо після збирання спостерігаються затримки чи нестабільна робота — припиніть експлуатацію та зверніться до фахівця.

Step-by-step instructions for cleaning daytime and nighttime optics

Матеріал підготовлено технічними редакторами «Торсен» спільно з оптиками-практиками. Мета — безпечне очищення лінз і корпусу прицілів, коліматорів, монокулярів ПНВ (PVS-14, BNVD) та тепловізорів без ризику мікроподряпин і пошкодження покриттів.

Before starting

• Work in a clean, dust-free area, wearing nitrile gloves; remove the batteries and allow the optics to cool to room temperature.
• Do not use household glass cleaners (ammonia, abrasives, surfactants), paper towels, or fabrics that shed lint.
• For thermal imagers with germanium lenses, use only compatible solutions directly recommended by the manufacturer (usually pure isopropyl alcohol or ethanol without additives).

What you will need

• Air blower for contactless dust removal.
• A soft antistatic brush or lens pen (brush) for gently sweeping away particles.
• Microfiber 200–300 GSM and/or disposable lint-free wipes for optics.
• The lens solution is pH-neutral and compatible with AR coatings/germanium (according to the manual).

Step 1. Contactless dust removal

1. Cover other surfaces and direct the air stream at an angle to the lens, 3–5 short puffs.
2. Do not breathe on the lens (condensation leaves salt stains). Keep compressed air cylinders at a distance of >20 cm and do not turn them upside down — propellant may leave marks.

Expert advice. A pear with an antistatic filter reduces dust accumulation on AR coatings.

Step 2. Gentle sweeping

1. Using a soft brush or paintbrush, gently sweep away any remaining particles from the center to the edge without applying pressure.
2. Clean the brush regularly to avoid transferring dust back onto the lens.

Step 3. Basic lens cleaning

1. Apply 1–2 drops of the special solution to a clean area of the microfiber cloth (not on the lens).
2. Wipe the lens with light circular motions from the center outwards. Use a new, clean section of the cloth for each circle.
3. Уникайте надлишку рідини — вона лишає розводи й може затягнути бруд під оправу.

Please note: AR coatings are thin (tens to hundreds of nanometers), so frequent "polishing" is harmful. Clean only when necessary.

Step 4. Drying and inspection

1. Leave the optics alone for 5–10 minutes to allow natural evaporation.
2. Check the lens under side lighting: if you see halos or streaks, repeat Step 3 with a minimal amount of solution.

Step 5. Cleaning the housing and fasteners

• Wipe the body with a soft, dry microfiber cloth; wipe the seams/gutters with cotton swabs without applying pressure.
• Ensure that there is no sand/dust in the mounting points (rings, plates, J-arm/dovetail); if necessary, remove and carefully wipe the mounting points.

Special precautions for PNV and thermal imagers

• PVS (PVS-14, BNVD). Lenses with magnesium fluoride/multilayer AR coatings — only optical solutions without ammonia/abrasives. Avoid getting chemicals on rubber eyecups and internal threads.
• Thermal imagers (germanium). Use only manufacturer-approved fluids (usually pure IPA/ethanol). Water, ammonia, and household "anti-fogging agents" can damage DLC/AR coatings.

Principles of operation and application: optics/thermal imaging — basic.

Useful techniques and facts

• Dust acts as an abrasive — always start with a non-contact stage (pear → brush) and only then move on to a napkin.
• Store your optics in a case with silica gel; before going out into the cold, allow the optics to acclimatize to avoid condensation inside.
• Do not clean "just in case": every extra rub increases the risk of micro-scratches.
• Remove rain/salt stains immediately after returning — they "eat into" the coating.

When to consult a specialist

Signs of fungus under the glass, rainbow spots/delamination of the coating, dust under the internal lenses, defocusing/collimation shift, "broken" pixels of the thermal imager matrix — reasons for servicing. Do not disassemble optical units yourself.

But if there is an urgent need — Guide to assembling and configuring PVS-14.

Prevention of pollution

100% protection against contamination is impossible, but systematic prevention significantly reduces risks, extends the service life of optics/weapons, and maintains stable image quality.

Prevention: what to do at all times

• Caps and covers. Keep lenses and eyepieces under caps; in the field, use quick-release caps/kill flashes.
• Clean environment. Work in a dust-free area, wearing nitrile gloves. Do not touch the lenses with your fingers — skin oils can damage the AR coating.
• The correct cleaning procedure. First, blow away the dust with a pear/soft brush without touching it, and only then move on to microfiber and solution — this way you will not turn the dust into an abrasive.
• Only compatible products. Avoid household "glass cleaners," ammonia, and abrasives; use wipes/liquids approved by the optics manufacturer.

Storage and moisture

• Airtight cases + silica gel. Keep equipment in airtight cases/safes with desiccant. Guideline: ≈1 g of silica gel per 1 L of internal volume (in humid climates — 2–3 g/L).
• Monitoring and regeneration. Use indicator silica gel; when it changes color, dry it in the oven and return it to the case.
• After rain/salt. Immediately remove drops/salt stains from the body; allow surfaces to dry before storing.

More about working underwater: Does the PNV work underwater?

Acclimatization without condensation

• Moving from cold to warm temperatures? Close the covers, place the optics in an airtight case/bag (with desiccant if possible) and do not open until the temperature has stabilized. This will minimize condensation on and inside the components.
• Do not accelerate heating/cooling with batteries, hair dryers, etc. — temperature shocks damage gaskets and adhesives.

Specially designed for night vision devices and thermal imagers

• Germanium lenses (thermal imagers): for cleaning, use only compatible isopropyl alcohol-based liquids (often 96% IPA or commercial compounds with ≥30% IPA); clean from the center to the edge and allow to dry on its own — do not "polish" dry.
• PVS (PVS-14, BNVD): AR coatings are very sensitive. Clean infrequently and only when necessary: pear → brush → 1–2 drops of optical solution on microfiber. Avoid getting chemicals on rubber eyecups and internal threads.
• Housing and fasteners: soft fabric; if necessary, a weak solution of detergent for the housing/cables, without aggressive chemicals.

Common mistakes (and how to avoid them)

• Dry cleaning of lenses. Always blow off dust first — otherwise, small particles will scratch the coating.
• "More liquid is better." Excess liquid leaves streaks and can drag dirt under the frame; 1–2 drops on a clean section of microfiber is sufficient.
• Mixing chemicals. Different formulas can neutralize each other or damage AR/DLC layers.
• Ignoring moisture. Without a desiccant in the case, you risk fungus and corrosion of contacts/coating.

Minimum prevention plan

• After each trip: blow off dust, wipe down the body, dry it, close the covers, and place it in a case with silica gel.
• Once every 2–4 weeks (or more often in humid conditions): check the color of the silica gel indicator and replace it.
• Before sudden temperature changes: take a "thermal break" in an airtight case/bag to avoid condensation.