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Henry Big Boy

• moderate
• Shop tier 3
• high confidence
• Rifle
• lever action
• tube magazine
• no loading gate
• pistol caliber
• cowboy action
• hunting

field strip ~5 min · reassembly ~8 min

Specifications

Model-specific safety

• Classic Henry rifles have no loading gate. They are loaded and unloaded through the inner magazine tube, which is withdrawn from the front of the outer tube under the barrel. If you are looking for a side gate, there may not be one — some later Henry models added one, many did not.
• Unloading means withdrawing the inner tube, rolling the cartridges out, and then cycling the action to clear the chamber and carrier. Three places to check.
• Tube magazines and pointed bullets do not mix. In a tube magazine a spitzer bullet tip rests against the primer of the round ahead of it, and recoil can set it off. Use flat-nose or approved polymer-tip ammunition only.
• The hammer has a half-cock position. Half-cock is a hammer rest, not a safety.
• Do not force the lever. If the action binds, something is out of position — usually the bolt or the carrier.

Under spring tension

• Magazine tube spring
• Hammer spring
• Carrier spring

Easily lost parts

Inner magazine tube · Lever pivot screw · Ejector spring

Tools

Shop difficulty

Shop tier 3 Tier 3 — hardest among rifles and carbines, for the full job: strip to the parts that get coated and put it back together working. 66 parts, with a trigger/hammer linkage of rocker, sear rocker spring, trigger lock and spring, transfer bar and link, plus a carrier dog, carrier dog spring and lever plunger. Henry says nothing past cleaning should be taken apart and sends further disassembly to a gunsmith. It is a lever action with a linked transfer-bar trigger, so it sits with the Marlins at the hard end of the rifle group, on thin outside evidence.

Parts: 66 numbered parts (Big Boy (H006, brass/silver receiver) list; H012 Steel list omitted), from Henry Big Boy — Instruction Manual for All H006 and H012 Series Rifles and Pistols — Henry Repeating Arms, p. 13 henryusa.com [1].

Bench time: about 50 min to strip, 80 min to rebuild (estimate). Estimate, set like the Marlins: lever and plunger, bolt (front/rear firing pins, extractor), carrier and dog, ejector, hammer/mainspring yoke, trigger guard plate with rocker, trigger lock, transfer bar and link, magazine tube, buttstock, forearm, sights. Rebuild longer for the trigger linkage springs and carrier dog.

Small parts: 10 pins, 9 springs, 5 detents or plungers (counted from the manufacturer's parts list (one per key number unless a quantity is given))

What comes off for coating

• Action: lever, lever plunger, spring and pin, bolt (front and rear firing pins, firing pin spring, retention pins, extractor and spring/plunger), carrier, carrier dog, pin and spring, carrier screw, ejector and spring, locking bolt and spring — pin punches
• Trigger guard plate: hammer, hammer screw, mainspring yoke and main spring, trigger, sear, rocker, trigger rocker link, trigger lock and spring, sear rocker spring, sear trigger pin, transfer bar and pin — pin punches
• Furniture: inner/outer magazine tube, follower, spring, knob, buttstock, buttplate, forearm, sights — brass drift for dovetail sights

Special tools

• Gunsmith screwdrivers — Lever, hammer, carrier, trigger guard plate and outer magazine screws (brass receiver mars easily)
• Pin punches — Sear trigger, transfer bar, carrier dog and lever plunger pins
• Brass/nylon drift — Dovetail sights

Known pain points

• Henry says the rifle is not to be taken apart past the manual and that further disassembly belongs to a gunsmith. (both)
  Source: Henry Big Boy — Instruction Manual for All H006 and H012 Series Rifles and Pistols — Henry Repeating Arms henryusa.com [1] — “Your firearm is a specialized, finely fitted mechanism. You may permanently damage it by attempting to disassemble the inner mechanisms.”
• The trigger group is a linkage of rocker, trigger lock, sear rocker spring, transfer bar and link that has to be reassembled under spring load to work as a transfer-bar safety. (reassembly)
  Source: Henry Big Boy — Instruction Manual for All H006 and H012 Series Rifles and Pistols — Henry Repeating Arms henryusa.com [1] — “Sear Rocker Spring”
• The carrier is driven by a sprung carrier dog on a pin, and the lever by a plunger and spring, both of which have to be held while their pins go in. (reassembly)
  Source: Henry Big Boy — Instruction Manual for All H006 and H012 Series Rifles and Pistols — Henry Repeating Arms henryusa.com [1] — “Lever Plunger Spring”

Fit or check on rebuild

• Transfer bar function — The hammer must not reach the firing pin unless the trigger is held back; check after reassembly
• Lever/carrier timing through the stroke — Carrier dog and lever plunger must lift and release the carrier cleanly
• Sight re-zero — Dovetail sights moved

This is Pew-Takedown's rating, not the manufacturer's. How tiers are rated. Forum reports are owners' experience, not specifications.

Manufacturer videos

Official videos from Henry Repeating Arms's own channels, linked rather than copied. Where a video and the steps on this page differ, follow the manufacturer's manual and video.

• Big Boy .44 Loading Henry Repeating Arms · plays on henryusa.com clearing, operation · 2013-01-17
  Covers: Henry H006 Big Boy .44 Magnum (brass receiver, tube-loading)
• Big Boy .44 Disassembly Henry Repeating Arms · plays on henryusa.com field strip · 2013-01-17
  Covers: Henry H006 Big Boy .44 Magnum
• Big Boy .44 Reassembly Henry Repeating Arms · plays on henryusa.com reassembly · 2013-01-17
  Covers: Henry H006 Big Boy .44 Magnum
• Big Boy .44 Cleaning and Lubrication Henry Repeating Arms · plays on henryusa.com cleaning, maintenance · 2013-01-17
  Covers: Henry H006 Big Boy .44 Magnum
• Big Boy .44 Safety Henry Repeating Arms · plays on henryusa.com operation · 2013-01-17
  Covers: Henry H006 Big Boy .44 Magnum
• How to Adjust Semi-Buckhorn Sights Henry Repeating Arms adjustment · 2016-07-19
  Covers: Henry rifles with semi-buckhorn rear sights ("found on the vast majority of our rifles" per the description)

Procedures

Torque specifications

No sourced torque values from the manufacturer are recorded for this firearm. Where a fastener has a specified torque — action screws, scope bases, muzzle devices, barrel nuts — get it from the manufacturer or a gunsmith rather than estimating it.

What the manufacturer does say: The manufacturer's documents give no torque value. They say: "Loosen the screw to the right of the white diamond, raise or lower as needed to correct elevation, then re-tighten the screw." (Henry Big Boy — Instruction Manual for All H006 and H012 Series Rifles and Pistols, PDF p. 9)

Reported by other sources — not the manufacturer

Materials and factory finish

As stated by Henry Repeating Arms. Prep, masking and cure depend on these; a polymer or aluminium part, a nitrided or anodised finish, and a blued steel part are each a different job. Variants with other finishes may exist — check the maker's page for the exact SKU on the bench.

Parts list

Transcribed from the manufacturer's parts list (Henry Big Boy — Instruction Manual for All H006 and H012 Series Rifles and Pistols — Henry Repeating Arms, p. 13 henryusa.com [1]) — Two separate lists: p.13 headed (H006) = brass/silver-receiver Big Boy, transcribed as the base model; p.14 headed (H012) = Big Boy Steel, omitted. Each series spans rifles, carbines and Mare's Leg pistols; no row is model-marked.. Key numbers refer to the exploded view in that document.

Function check

• Verify the rifle is unloaded — chamber, carrier, and magazine tube — before each step.
• Cycle the lever fully and confirm the bolt locks up with the lever closed.
• With the hammer cocked, engage the safety if fitted and press the trigger. The hammer must not fall.
• Disengage the safety and press the trigger. The hammer should fall.
• Confirm the lever safety, where fitted, prevents firing with the lever not fully closed.
• Load dummy rounds through the magazine tube and cycle them, confirming they feed from the carrier and eject cleanly.
• Confirm the inner magazine tube latches securely.

Maintenance

Lubrication points

• Bolt body and locking block
• Lever camming surfaces
• Carrier pivot
• Hammer and sear pivots
• Magazine tube exterior

Cleaning notes

Keep the inside of the magazine tube dry rather than oiled — oil there collects fouling and slows the follower. Clean from the breech with a bore guide where the action allows it.

Suggested inspection interval: roughly every 500 rounds. This is a general guideline, not a manufacturer specification.

Wear parts to inspect

Extractor · Ejector and spring · Carrier · Magazine spring · Loading gate spring where fitted

Common issues

Also covers

The procedures above are reported to apply to: Big Boy Steel · Big Boy Classic. Verify against the manual for your specific model.

Similar manual of arms

• Marlin Model 336
• Rossi R92

Sourcing