Torque wrench · ft-lb
CDI / Tekton Torque Wrench (ft-lb)
- ✓1/2 inch drive for barrel nuts
- ✓Essential for upper assembly
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ToolsAR-15Builds
AR-15 Build Tools 2026: Complete Kit List ($100 Budget to $500 Pro Setup)
The right tools make the difference between a rifle that runs and one that doesn't. This guide covers every tool you need to build, maintain, and mount optics on AR-pattern rifles, plus when and how to use each one.
Assumes knowledge of
How to Build an AR-15->Quick Answer: What tools do you need to build an AR-15?
Essential for any build: Armorer's wrench, punch set, vise blocks, and torque wrenches (both ft-lb and in-lb). Budget $150-200 for starter kit.
For optics: Add inch-pound torque driver, scope leveling system, and Loctite. Total ~$50-75.
Quality matters: Buy once, cry once. Good tools last decades. Avoid Harbor Freight for torque-critical applications.
Tool investment philosophy
- • Buy once, cry once. Quality tools last decades and pay for themselves over a few builds.
- • Start with the essentials. You don't need everything at once, so prioritize based on your first project.
- • Torque specs matter. Under-torqued screws walk loose; over-torqued screws strip or break. A good torque wrench is non-negotiable.
Assembly Tools: The Non-Negotiables
These are the foundational tools for any AR build. Whether you're assembling a lower receiver or installing a handguard, you'll reach for these constantly.
Armorer's Wrench
A multi-purpose wrench designed for AR-15 castle nuts, barrel nuts, and free-float handguard installation. Look for one that fits MIL-SPEC castle nuts and has provisions for common barrel nuts.
When to use it
- • Tightening and staking castle nuts (35–40 ft-lbs)
- • Installing barrel nuts (30–80 ft-lbs depending on design)
- • Installing free-float handguards with proprietary barrel nuts
- • Removing flash hiders and muzzle devices
Pro tip
Get a wrench with a built-in torque adapter or pair it with a 1/2" drive torque wrench. The Magpul Armorer's Wrench and Real Avid Master-Fit are both solid choices that cover most barrel nut styles.
Punch Set
Roll pin punches, starter punches, and pin punches in various sizes for driving out and installing pivot pins, trigger pins, and detent pins. Brass or polymer-tipped punches prevent marring on finished receivers.
Essential sizes
- • 1/16": Detent pins, gas block set screws
- • 3/32": Trigger pins, hammer pins
- • 5/32": Pivot/takedown pins, bolt catch roll pin
- • Roll pin starters: For seating roll pins without mushrooming
Pro tip
Use a roll pin holder or needle-nose pliers to start roll pins. Striking them directly with a punch often leads to bent pins or marred receivers. The Wheeler Roll Pin Install Tool Kit makes this nearly foolproof.
Vise Blocks
Clamshell blocks that hold upper or lower receivers securely in a bench vise without damaging the finish. Upper vise blocks fit the magazine well; lower blocks clamp around the receiver body or use the takedown pin holes.
When to use each type
- • Upper vise block: Installing barrels, barrel nuts, handguards, muzzle devices
- • Lower vise block: Installing castle nuts, buffer tube assemblies (less common)
- • Reaction rod (BEV Block): Absorbs barrel nut torque through the barrel extension, not the upper receiver index pin
Warning
Standard clamshell upper vise blocks transfer barrel nut torque through the receiver's index pin. For high-torque barrel nuts (50+ ft-lbs), use a reaction rod or Geissele Super Reaction Rod that loads the barrel extension lugs instead. This prevents cracking the upper receiver.
Torque Wrenches
You need two types: a foot-pound wrench for barrel nuts and castle nuts, and an inch-pound wrench for optic mounts, gas block screws, and grip screws. Digital or click-type both work, so pick what fits your budget.
Recommended specifications
- • Foot-pound wrench: 10–80 ft-lbs range, 1/2" drive for armorer's wrench compatibility
- • Inch-pound wrench: 10–65 in-lbs range, 1/4" drive with bit adapter
- • Wheeler FAT Stix: Preset torque limiters for common values (15, 25, 35, 65 in-lbs)
Multi-tool wrench
Magpul Armorer's Wrench
- ✓Fits MIL-SPEC and most proprietary barrel nuts
- ✓Built-in torque wrench adapter
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Multi-tool wrench
Real Avid Master-Fit AR-15 Armorer's Wrench
- ✓Interchangeable barrel nut heads
- ✓Includes castle nut and A2 front sight tools
$329.99
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Punch set
Wheeler Master Roll Pin Punch Set
- ✓Includes roll pin starters
- ✓Brass drifts protect finish
$49.99
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Punch set
Real Avid Accu-Punch Set
- ✓Multiple tip materials
- ✓Storage case keeps sizes organized
$45.99
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Reaction rod / vise block
Geissele Super Reaction Rod
- ✓Protects upper receiver from torque stress
- ✓Works with all standard AR uppers
$147.49
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Vise block
Magpul BEV Block
- ✓Works on uppers and lowers
- ✓Lighter than steel reaction rods
$46.95
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Front sight tool
A2 Front Sight Adjustment Tool
- ✓Four-prong design fits A2 sight post
- ✓Required for zeroing iron sights
Check Price at OpticsPlanet
Gas block alignment
Gas Block Alignment Rod
- ✓Centers gas block over gas port precisely
- ✓Prevents gas leak from misaligned installation
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Purchasing through these links may generate a commission at no extra cost to you. Always verify torque specs for your specific components.
Optic Installation Tools
Mounting optics correctly requires precision. A crooked reticle or improperly torqued rings will cost you accuracy and repeatability. These tools ensure your optic is level, properly torqued, and stays put through thousands of rounds.
Scope Leveling System
A canted reticle introduces tracking errors that compound at distance. Leveling systems use dual bubbles or laser projection to align the scope reticle with the rifle's bore axis before you torque the rings.
How to use
- Level the rifle in a stable rest or vise
- Place the barrel-mounted reference level and zero it
- Set the scope in under-torqued rings
- Place the scope-mounted level on the turret cap or elevation turret
- Rotate the scope until both bubbles are centered
- Torque ring screws in a cross pattern to spec
Inch-Pound Torque Driver
Optic mount screws, ring screws, and red dot mounting screws all require precise inch-pound torque values. Over-torquing can crack scope tubes, strip threads, or warp red dot housings.
Common torque specs
- • Scope ring screws: 15–25 in-lbs (follow manufacturer spec)
- • Red dot mounting screws: 15–20 in-lbs
- • Picatinny mount cross-bolts: 25–35 in-lbs
- • One-piece mount screws: Per manufacturer (often 18–25 in-lbs)
Pro tip
The Wheeler FAT Stix set includes preset torque limiters at common values. Pop in the right stick, turn until it clicks, and you're at spec. Faster than adjusting a wrench and nearly impossible to over-torque.
Threadlocker & Anti-Seize
Blue Loctite (242/243) is your go-to for optic mount screws, gas block screws, and grip screws. It prevents vibration loosening while remaining removable with hand tools. Anti-seize is used on dissimilar metals (steel screws in aluminum mounts) to prevent galling.
When to use what
- • Blue Loctite: Ring screws, red dot screws, gas block screws, grip screws
- • Purple Loctite (222): Small set screws, adjustment screws (lower strength)
- • Anti-seize: Steel screws into aluminum (prevents thread seizing)
- • Rocksett: Muzzle devices, especially for suppressor compatibility
Modular torque set
Fix It Sticks Torque Kit
- ✓Modular—buy only the values you need
- ✓Extremely portable for range/field use
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Scope leveling kit
Wheeler Professional Reticle Leveling System
- ✓Two-level system eliminates cant error
- ✓Works with LPVOs and precision scopes
$59.99
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Threadlocker
Loctite Blue 242 Threadlocker
- ✓Removable with hand tools
- ✓Essential for any screw that sees recoil
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Complete mounting kit
Vortex Optics Mounting Kit
- ✓All-in-one kit for first-time mounters
- ✓Includes alignment rods for ring centering
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Preset torque limiters
Wheeler F.A.T. Stix Torque Wrench Set
- ✓Preset values prevent guessing
- ✓Compact roll for range bags
$99.99
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Scope leveling kit
Real Avid Level-Right PRO
- ✓Laser projection for quick alignment
- ✓Works with all magnified optics
$79.99
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Threadlocker
Loctite 243 Blue Threadlocker
- ✓Removable with hand tools
- ✓Essential for any screw that sees recoil
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Purchasing through these links may generate a commission at no extra cost to you. Always follow manufacturer torque specs for your specific optic.
Diagnostics & Quality Control
These tools help you verify safety-critical dimensions and inspect wear over time. Essential for armorers managing multiple rifles or anyone building from parts.
Headspace Gauges
Headspace is the distance from the bolt face to the chamber shoulder that stops the cartridge. Incorrect headspace can cause case head separations, extraction failures, or dangerous pressure spikes. Check headspace when swapping bolts or barrels.
How to check headspace
- Remove the firing pin and extractor from the bolt
- Insert the GO gauge into the chamber
- Close the bolt: it should close fully on the GO gauge
- Insert the NO-GO gauge
- Close the bolt: it should NOT close on the NO-GO gauge
Safety critical
If the bolt closes on a NO-GO gauge, the rifle has excessive headspace and is unsafe to fire. Do not use it until you've replaced the barrel or bolt to bring headspace into spec. A FIELD gauge represents the maximum safe limit: if it closes on that, stop immediately.
Borescope
A digital borescope lets you inspect the bore, chamber, throat erosionThroat Erosion[Barrel]Gradual wear at the chamber end of the barrel from hot propellant gases. Affects accuracy over thousands of rounds by changing the bullet's jump to the rifling., and gas port condition without disassembly. Side-view probes are ideal for AR barrels since they let you see the rifling lands and grooves clearly.
What to look for
- • Throat erosion: Fire-cracking ahead of the chamber indicates high round counts
- • Pitting or corrosion: Indicates poor cleaning or corrosive ammo residue
- • Copper fouling: Blue/green streaks in rifling grooves
- • Crown damage: Nicks or erosion at the muzzle affect accuracy
Bore Guide & Cleaning Rod
Always clean from chamber to muzzle. A bore guide centers the cleaning rod in the receiver and prevents solvent from seeping into the action. Carbon fiber rods won't embed grit like steel rods can.
Pro tip
Tipton's carbon fiber rods with bearing handles follow the rifling twist automatically, reducing rod flex and wear on the crown. Pair with a quality bore guide and you'll never damage your throat with a cleaning rod again.
Headspace gauge
5.56 Headspace Gauge Set (GO/NO-GO)
- ✓Essential for bolt/barrel swaps
- ✓Prevents dangerous overpressure conditions
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Borescope
Teslong Rifle Borescope (Side-View)
- ✓Side-view shows rifling lands clearly
- ✓Records photos/video for trend tracking
$209.99
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Bore guide
Tipton AR-15 Bore Guide
- ✓Prevents rod wear on throat
- ✓Keeps solvent in the barrel where it belongs
$23.89
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Cleaning rod
Tipton Deluxe Carbon Fiber Cleaning Rod
- ✓Won't scratch bore like steel rods
- ✓Ball bearing handle follows rifling twist
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Carbon scraper
Otis B.O.N.E. Tool Bolt Scraper
- ✓Designed specifically for AR BCGs
- ✓Reaches cam pin pocket and bolt tail
$31.99
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Cleaning rod
Tipton Deluxe Carbon Fiber Cleaning Rod
- ✓Won't scratch bore
- ✓Ball bearing handle follows twist
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Bore guide
AR-15 Bore Guide
- ✓Prevents rod wear on throat
- ✓Keeps solvent in the barrel where it belongs
$32.52
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Purchasing through these links may generate a commission at no extra cost to you. Consult a qualified armorer if you're unsure about inspection results.
Consumables & Lubricants
These products get used up over time but make assembly reliable and keep rifles running. Stock up on the essentials and rotate through your supply.
Threadlockers
- • Blue Loctite 242/243: Gas blocks, optic mounts, grip screws
- • Purple Loctite 222: Small adjustment screws
- • Rocksett: Muzzle devices (water-soluble, high temp)
Lubricants
- • CLP: General cleaning, light lube, corrosion protection
- • Aeroshell 33MS: Barrel nut threads, anti-galling paste
- • Grease: Buffer tube threads, charging handle rails
Cleaning Supplies
- • Bore solvent: Breakthrough Clean, Hoppe's #9
- • Copper remover: For stubborn copper fouling
- • Carbon scraper: Bolt tail, cam pin pocket
Replacement Parts
- • Spare detent springs: Selector and buffer retainer
- • Gas rings: Replace when BCG tilts in upper
- • Extractor springs: Factory spares or upgraded kits
CLP
Breakthrough Clean CLP
- ✓Odorless—no ventilation required
- ✓Safe on all metal finishes
$20.99
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Copper solvent
Hoppe's Copper Solvent
- ✓Attacks copper fouling specifically
- ✓Use after heavy range sessions
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Muzzle device adhesive
Rocksett High-Temp Adhesive
- ✓Suppressor-safe
- ✓Remove by soaking in water 24hr
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Anti-galling grease
Aeroshell 33MS Grease
- ✓Prevents thread galling
- ✓MIL-SPEC G-23827
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CLP
Breakthrough Clean Military-Grade Solvent
- ✓Odorless—no ventilation required
- ✓Safe on all metal finishes
$20.89
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Lubricant
Slip 2000 EWL
- ✓Synthetic—survives suppressor heat
- ✓Won't gum up in cold weather
$34.89
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Spare parts
AR-15 Detent & Spring Kit
- ✓Essential spares for any build
- ✓Lost springs are inevitable—stock up
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Purchasing through these links may generate a commission at no extra cost to you. Store chemicals per manufacturer guidelines.
Field & Range Cleaning
There's a difference between bench cleaning (thorough, periodic, rod-and-bore-guide work) and field cleaning (quick, between sessions, keep-it-running work). Both matter, but field cleaning prevents carbon from hardening into the bore and keeps your rifle cycling reliably during extended range days.
Pull-Through Cleaners
A boresnake or pull-through cleaner is the fastest way to run a pass through the bore at the range. Drop the weighted cord in from the chamber end, pull through, and you've displaced the worst of the carbon in under 30 seconds. The Hoppe's BoreSnake Viper has a built-in bronze brush section that scrubs fouling on the way through. The Otis Ripcord uses Nomex fiber that resists heat up to 1,000 degrees F, outlasting cotton-based alternatives.
Pro tip
Run a boresnake after every range session. It takes 30 seconds and prevents carbon from hardening into the bore. This is not a replacement for proper rod cleaning, but it extends the interval between deep cleans significantly.
Chamber & Gas System
Carbon buildup in the star chamber and gas tube causes cycling issues that a boresnake can't reach. Dedicated chamber cleaning tools have star-shaped bristles that match the chamber lug recesses, while gas tube cleaners use flexible wire brushes to clear carbon deposits from the gas system. Neglecting these areas is a common cause of short-stroking and failure to extract.
Field Cleaning Setup
A complete field cleaning kit fits in a gallon zip-lock bag: cleaning mat, pull-through cleaner, CLP, a few patches, and a chamber brush. The cleaning mat protects your bench or tailgate from solvent damage while giving you a visual reference for parts during disassembly.
Pull-through cleaner
BoreSnake
- ✓One-pass cleaning at the range
- ✓Built-in brush scrubs carbon and fouling
Check Price at OpticsPlanet
Premium pull-through
Otis Ripcord Bore Cleaner
- ✓Nomex fiber resists heat to 1,000 deg F
- ✓Outlasts cotton pull-throughs significantly
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Cleaning cable
Otis Small Caliber Cleaning Cable
- ✓Breech-to-muzzle cleaning direction
- ✓Memory-flex cable navigates bore easily
$12.99
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Bore brushes
Otis Bronze Bore Brushes
- ✓Bronze bristles scrub carbon rings
- ✓8-32 thread fits Otis cleaning systems
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Chamber & gas cleaning
Chamber & Gas System Cleaning Kit
- ✓Star chamber tool reaches carbon deposits
- ✓Gas tube cleaner maintains reliable cycling
Check Price at OpticsPlanet
Field CLP
Duty-Grade CLP
- ✓Quick application between sessions
- ✓All-in-one clean, lube, and protect
Check Price at OpticsPlanet
Cleaning mat
TekMat AR-15 Cleaning Mat
- ✓Protects surfaces from solvent damage
- ✓AR-15 diagram helps identify parts during disassembly
$25.99
Check Price at OpticsPlanet
Purchasing through these links may generate a commission at no extra cost to you.
Quick Reference: Complete Torque Specs
Foot-Pound Values
- Castle nut: 35–40 ft-lbs (then stake)
- Standard barrel nut: 30–80 ft-lbs
- Muzzle device: 15–20 ft-lbs (or crush washer)
- Buffer tube: Hand tight + 3 notches staked
Inch-Pound Values
- Gas block screws: 25–35 in-lbs
- Grip screw: 40–45 in-lbs
- Scope ring screws: 15–25 in-lbs
- Red dot mount: 15–20 in-lbs
- Picatinny cross-bolts: 25–35 in-lbs
Always check manufacturer specs, as some proprietary systems (Geissele, BCM, LaRue) have different requirements. When in doubt, start at the low end of the range and verify the fastener holds under recoil before going higher.
Budget tiers: What to buy first
First Build Kit (~$150–200)
- • Wheeler AR Armorer's Essentials Kit (wrench, punches, vise block)
- • Wheeler FAT Stix torque set
- • Blue Loctite 242/243
- • Basic CLP and cleaning kit
Serious Builder Kit (~$300–400)
- • Magpul or Real Avid Armorer's Wrench
- • Real Avid punch set with roll pin tools
- • Geissele Super Reaction Rod
- • CDI or Tekton torque wrenches (both in-lb and ft-lb)
- • Scope leveling kit
- • 5.56 headspace gauge set
Armorer/Fleet Kit (~$600+)
- • All of the above plus:
- • Digital borescope with side-view probe
- • .308/7.62 headspace gauges
- • Barrel timing/indexing tools
- • Spare parts organizer with common replacement items
Starter kit
Wheeler AR Armorer's Essentials Kit
- ✓Good starter kit for first builds
- ✓Includes most essential tools
$102.99
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Professional kit
Real Avid AR-15 Armorer's Master Kit
- ✓Professional-grade tools
- ✓Organized storage case included
$89.99
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Budget kit
NcSTAR AR-15 Tool Kit
- ✓Budget-friendly entry point
- ✓Upgrade key tools as you go
$61.99
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Purchasing through these links may generate a commission at no extra cost to you. Individual tool quality may vary—upgrade key items as needed.
Range Bag Multi-Tool
A quality multi-tool in your range bag handles the quick fixes that would otherwise end your range session: loose screws, stuck pins, frayed slings. The Leatherman MUT is the only multi-tool designed specifically for the AR platform, with a bronze carbon scraper, bolt override tool, and military-spec disassembly punch built in.
Leatherman Leatherman MUT (Military Utility Tool)
Best multi-tool for AR owners
16 toolsBolt override toolBronze carbon scraper
Purpose-built tactical multi-tool for AR-15/M4 maintenance. Includes bolt override, carbon scraper, and replaceable firearm-specific bits.
Pros
- +Only multi-tool with AR-specific bolt override tool
- +Bronze scraper won't damage bolt finish
- +Replaceable bits cover common firearm fasteners
- +Robust construction handles actual field use
- +MOLLE sheath secures tool during movement
Cons
- -Heavier than general-purpose multi-tools (11.6 oz)
- -Premium price point (~$180)
- -Firearm-specific tools less useful for non-AR owners
- -Some users prefer the EOD variant's C4 punch
- -Bit driver requires practice to use efficiently
Tool Count: 16 toolsClosed Length: 5"Weight: 11.6 oz (with bit kit)Blade Material: 154CM stainless steel
Looking for more options? See our full Best Tactical Multi-Tools guide for rankings and detailed comparisons across 10+ models.
Training & Dry Fire Tools
Dry fire is the most cost-effective way to improve shooting fundamentals. Zero ammo cost, practice at home, and build the neural pathways that transfer directly to live fire performance. These tools add feedback and measurement to what would otherwise be guesswork.
Safety critical
Always verify the firearm is completely unloaded before dry fire practice. Remove all live ammunition from the training area. Check the chamber visually and physically. Then check it again.
Dry Fire Essentials
Snap caps protect the firing pin during dry fire practice (though the AR-15 firing pin handles dry fire fine without them) and double as malfunction clearing training aids. Laser training cartridges add visual feedback: pull the trigger and a visible laser indicates exactly where you would have hit. Pair them with reactive laser targets for an interactive training loop without leaving home.
Shooting Diagnostics
The Mantis X sensor attaches to your accessory rail and detects micro-movements during the trigger press that are invisible to the naked eye. The companion app shows movement patterns, scores each trigger pull, and tracks improvement over time. It works in both dry fire and live fire modes.
Shot Timers
A shot timer is the single best training investment after ammunition. It measures what your perception can't: actual split times, draw-to-first-shot, and transitions between targets. Par time programming lets you set goals and train against them. You can't improve what you don't measure.
Pro tip
Combine the Mantis X with dry fire snap caps for the most effective home training setup. 15 minutes of focused dry fire daily beats 500 rounds of unfocused live fire.
Shooting diagnostics
Mantis X10 Elite Training System
- ✓Real-time feedback on trigger control and movement
- ✓Works in both live fire and dry fire modes
Check Price at OpticsPlanet
Laser dry fire cartridge
LaserLyte 5.56 Training Cartridge
- ✓Visible laser on trigger pull for instant feedback
- ✓Works with reactive laser targets
$59.99
Check Price at OpticsPlanet
Snap caps
ST-2 Snap Caps
- ✓Protects firing pin during dry fire practice
- ✓Also useful for malfunction clearing drills
Check Price at OpticsPlanet
Shot timer
PACT Club Timer III
- ✓Par time programming for self-paced drills
- ✓Measures split times and draw-to-fire
$129.95
Check Price at OpticsPlanet
Purchasing through these links may generate a commission at no extra cost to you.
Range Bag Essentials
A well-stocked range bag prevents wasted trips and keeps you shooting instead of troubleshooting. These are the supporting items you should always have packed and ready to go.
Hearing & Eye Protection
Electronic ear protection is worth the upgrade over passive muffs. It amplifies range commands and conversation while instantly blocking gunshots, which means you can communicate during instruction and hear range safety commands clearly. Eye protection is non-negotiable: ANSI Z87.1-rated shooting glasses protect against ejected brass, debris, and the rare catastrophic failure.
Zeroing & Targets
Proper zeroing targets with 1-inch grid patterns make adjustment calculations straightforward: count the squares from point of aim to point of impact, convert to MOAMOA[Optics]Minute of Angle. At 100 yards, 1 MOA ≈ 1 inch. Used to measure rifle accuracy (e.g., '1 MOA rifle') and adjustment clicks on scopes. or MIL, and dial it in. Keep a few in the range bag at all times so you can re-confirm zero whenever you swap optics or after transport.
Transport
Two options depending on context: a standard padded soft case for range trips (lighter, more pockets, easier to carry), and a discreet-profile case with backpack straps for urban settings where you prefer not to advertise. Hard cases are better for airline travel and long-term storage but are overkill for local range trips.
Pro tip
Keep a chamber flag in your range bag. Many ranges require visible empty chamber indicators during cease-fires, and all competition stages require them. They cost almost nothing and prevent awkward conversations with range officers.
Hearing protection
Electronic Ear Protection
- ✓Amplifies range commands while blocking gunshots
- ✓Essential for communication during instruction
Check Price at OpticsPlanet
Zeroing targets
Zeroing Targets
- ✓Grid pattern calculates MOA/MIL adjustments
- ✓High visibility for easy shot identification
Check Price at OpticsPlanet
Safety flag
Chamber Safety Flag (5-Pack)
- ✓Required at most ranges and all competitions
- ✓Visible indicator that the firearm is clear
Check Price at OpticsPlanet
Soft rifle case
Soft Rifle Case
- ✓Padded protection during transport
- ✓Multiple pockets for accessories
Check Price at OpticsPlanet
Discreet rifle case
Discreet Rifle Case
- ✓Low-profile appearance for urban transport
- ✓Backpack straps for hands-free carry
Check Price at OpticsPlanet
Purchasing through these links may generate a commission at no extra cost to you.
Next steps
Got your tools? Put them to work with our other guides:
- • Build Your First AR – Step-by-step lower assembly and upper pairing
- • Optic Mounting Basics – Proper installation and torque procedures
- • Maintenance & Armorer Schedule – Inspection intervals and replacement schedules
- • Gas System & Buffer Tuning – Dial in your cycling for suppressed or unsuppressed use
Disclaimer
This guide is for educational purposes. Always follow manufacturer instructions and torque specifications for your specific components. If you're unsure about any procedure, consult a qualified armorer or gunsmith. Purchasing through affiliate links may generate a commission at no extra cost to you.
Frequently Asked Questions
▶What tools do I need to build an AR-15?
Essential tools: armorer wrench, punch set, torque wrench (15-80 ft-lb range), upper receiver vise block, lower receiver vise block, roll pin starter punches. Nice to have: reaction rod, barrel nut wrench specific to your handguard, headspace gauges. Budget $150-300 for quality tools.
▶What tools are essential for AR-15 maintenance?
For regular maintenance: bore snake or cleaning rod, nylon brushes, CLP or gun oil, cotton patches, carbon scraper, and a basic punch set for disassembly. For deeper work: bolt carrier group scraper tool, chamber brush, and dental picks for carbon removal. Most AR-15 field maintenance requires no special tools beyond a punch set and basic cleaning supplies. Budget $40-80 for a complete maintenance kit.
▶What's included in an AR-15 tool kit?
A complete AR-15 tool kit includes: armorer wrench (castle nut/barrel nut/muzzle), punch set (1/16" to 3/16"), torque wrench (15-80 ft-lb), upper vise block, lower vise block or mag well block, roll pin starter punches, and pivot pin installation tool. Premium kits add: reaction rod, gas tube alignment tool, headspace gauges, and carrying case. Real Avid, Wheeler, and Magpul make quality kits in the $150-300 range.
▶What torque for AR-15 barrel nut?
Standard mil-spec barrel nuts: 30-80 ft-lb, torqued until the gas tube hole aligns (usually 35-50 ft-lb). Free-float handguards vary, so check manufacturer specs. Most are 25-55 ft-lb with timing requirements. Always use a torque wrench, not a breaker bar.
▶Do I need headspace gauges for AR-15?
For factory barrels/BCGs: no, they're headspaced at the factory. For used parts, mixing brands, or after bolt replacement: yes, check with GO and NO-GO gauges. A FIELD gauge checks for unsafe headspace that requires immediate attention. Cost is $50-80 for a quality set.
▶What is the best AR-15 armorer wrench?
The Magpul Armorer's Wrench is the best value at $35-45: it handles castle nuts, barrel nuts, and muzzle devices. Geissele, Real Avid, and Wheeler make premium options. Avoid cheap Amazon wrenches that flex or round off castle nuts.
▶How do I remove a stuck muzzle device?
Heat with propane torch (not on the barrel), apply penetrating oil, use a proper armorer wrench with the upper in a reaction rod or vise block. Crush washers may need to be cut off. Rocksett requires heat to 500°F+ to release. Never use pipe wrenches: they damage flats.
▶What torque for optic mounts?
Varies by mount, so check manufacturer specs. Common values: Picatinny rail screws 25-35 in-lb, scope ring screws 15-25 in-lb (don't overtorque), red dot mounts 15-25 in-lb. Use a FAT wrench or similar for inch-pound torque. Blue Loctite on hardware.
▶What should I keep in my AR-15 range bag?
Essentials: boresnake or pull-through cleaner, CLP, electronic ear pro, eye protection, zeroing targets, chamber flags, a multi-tool, spare batteries, snap caps for dry fire, and a cleaning mat. Keep a soft case for transport and chamber flags for range cease-fires. A shot timer is the single best training investment after ammunition.
▶Is dry fire practice safe for an AR-15?
Yes. The AR-15 firing pin is designed to handle dry firing without damage. Using snap caps provides extra protection and allows malfunction clearing practice. Always verify the firearm is completely unloaded and remove all live ammunition from the training area before dry fire practice.
Complete Your Build
Essential accessories to round out your setup
Scroll
Next Step
Ready to continue? Here's the recommended next guide:
Recommended Next
AR-15 Optic Selection 2026: Red Dot vs LPVO vs Prism vs Magnifier Compared
Choose the best AR-15 optic for your mission. Compare red dots, LPVOs (1-6x, 1-8x), prism scopes, and magnifier setups with weight data, mounting heights, and use-case decision tables.
Or explore a related topic:
AR-15 Maintenance Schedule 2026->
ABAuthor
Avid shooter with 9+ years of experience including competition shooting. Built 10+ AR-pattern rifles and several handgun platforms for home defense, competition, and suppressed night shooting.
9+ years shooting experienceCompetition shooterBuilt 10+ AR-pattern rifles
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AR-15Builds
How to Build an AR-15: Complete Parts List & Step-by-Step Guide (2026)
Complete 2026 guide on how to build an AR-15 from a stripped lower with full parts list, tools needed, and step-by-step assembly. Budget tiers from PSA ($600) to Geissele ($1,600) with FFL transfer, lower parts kit, and complete upper selection.
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AR-15Optics
AR-15 Optic Mounting 2026: Complete Guide (Red Dots, Scopes, Accessories)
Learn proper AR-15 optic mounting with practical steps for eye relief, rail placement, threadlocker application, torque specs, and accessory positioning for repeatable zero.
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AR-15Builds
Lightweight AR-15 Build 2026: Cut Weight Without Losing Reliability
Trim AR-15 weight where it matters. Choose lighter barrels, rails, and stocks (including KP-15 polymer lowers), then set up optics, lasers, lights, and suppressors to avoid front-heaviness.
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Latest News & Reviews
Related articles and industry updates
ReviewAS Designs
AS Designs ARC-Fire Review: 400 Rounds on the SIG MCX Spear LT
Hands-on review of the AS Designs ARC-Fire forced reset selector after 400 suppressed rounds on a SIG MCX Spear LT 11.5 with Geissele SSA-E. MCX install tips, safety selector complaints, and comparison to Partisan Disruptor.
Feb 1710 min
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ComparisonAR-15
Best Forced Reset Triggers & Super Safeties 2026: Buyer's Guide
Complete comparison of forced reset triggers and super safeties for AR-15: Partisan Disruptor FRT, Arc Fire, Atrius FRS, and Mars Super Safety. Performance, pricing, legality, and which system fits your build.
Feb 912 min
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ReviewAR-15
Atrius FRS Review: Drop-In Forced Reset Selector for AR-15
The Atrius FRS is a drop-in forced reset selector that delivers rapid semi-auto fire at $249. Unlike FRT triggers, it works with your existing mil-spec FCG and reduces rifle wear.
Feb 49 min
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