GAMES2PEOPLE Armstrong Replacement Lock for Stack-On Safes, Brass Finish, Direct Replacement Key Lock for Current Stack-On and Sentinel Gun Cabinets, Weather Resistant with 2 Keys and Mounting Hardware

Why I reached for this lock

My Stack-On cabinet’s original key lock had started to bind and felt sloppy after years in a garage. Rather than retiring a perfectly good cabinet, I picked up the Armstrong replacement lock—a brass-finished, direct-fit swap for current Stack-On and Sentinel gun cabinets. I wanted something I could install myself without fuss, matched the existing hardware, and wouldn’t mind a bit of humidity. This lock checked those boxes: brass finish, weather-resistant coating, two matching keys, and all the mounting hardware in the bag.

Fit and compatibility

Compatibility is the make-or-break point with cabinet locks, and this one is purpose-built for current Stack-On and Sentinel models that use a standard flat key cam lock. If your cabinet uses:

• An older tubular key lock
• A small personal pistol box format
• A dial or electronic keypad

this isn’t the right part. For current flat-key cam-lock models, though, it’s a straight replacement. On my cabinet, the lock cylinder length and cam travel matched what was there, so the latch alignment and door seal pressure remained unchanged. If you’re not sure which you have, check the key type and look at the inside of the door: you should see a simple cam that rotates to catch behind the frame. That’s the setup this lock expects.

Installation: simple and quick

From door-open to lockable, I spent roughly 10–15 minutes on the swap. The process is straightforward:

1. Open the door and remove the inside trim or panel if your cabinet has one (many use simple screws).
2. Note the orientation of the existing cam and which hole the cam uses on the back of the lock (take a quick photo).
3. Loosen and remove the retaining nut on the old lock. Slide out the old cylinder from the front.
4. Insert the new cylinder from the front, aligning it so the key position makes sense for your preferred “locked/unlocked” orientation.
5. Install the cam on the back of the new lock in the same hole and orientation as your original.
6. Thread on the retaining nut and snug it—firm, but not gorilla-tight. Test the action before you reassemble the inner panel.

Tools I used:
- Small adjustable wrench or deep socket for the retaining nut
- Screwdriver for the inner panel
- Optional: a tiny dab of medium threadlocker or a star washer to keep the nut from backing off over time

One tip: test the lock through several cycles with the door open—lock, unlock, and pull the handle—to confirm the cam engages cleanly without rubbing. If you feel binding, move the cam to the alternate mounting hole (if available) or recheck the orientation.

Build quality and finish

The big cosmetic win is the brass finish. It dresses up a utilitarian cabinet and pairs nicely with darker paint. Beyond looks, the finish has shrugged off fingerprints and the occasional damp garage day without spotting or tarnish so far. It isn’t a solid-brass, heirloom lock; this is a practical replacement part that aims to match the OEM standard.

Out of the box, the keying was clean with no burrs, and both included keys operated the cylinder. The action on mine felt a touch tight for the first few turns, then smoothed out after half a dozen cycles. That’s typical of new cam locks. If you encounter stiffness, a puff of powdered graphite in the keyway helps; avoid oil-based lubricants, which can gum up over time.

The cam and hardware are serviceable and fit as expected. I do have one caution: don’t overtighten the retaining nut. Cam lock shafts are often zinc alloy, and excessive torque can stress threads or the neck. Snug is enough. If you’re worried about the nut loosening, use threadlocker or a lock washer rather than extra force.

Security expectations, set correctly

This lock is designed to maintain the security profile of a standard Stack-On/Sentinel cabinet—nothing more, nothing less. You’re not upgrading a cabinet into a high-security safe with this swap; you’re restoring proper function and key control. Within that context, the lock does its job well: consistent engagement, clear key indexing, and solid closure against the frame.

If you need higher security (e.g., tamper-resistant cylinders, hardened cams, or audit controls), you’re shopping in a different segment. For a household gun cabinet in a controlled environment, this is a sensible, dependable repair.

Daily use and reliability

After installation, I cycled the lock twice a day for a week before loading the cabinet. The key insertion is positive and centered, and a quarter turn locks and unlocks without drama. The cam meets the strike squarely, and the handle travel remained unchanged from the original hardware—important for door alignment and gasket compression. The finish has resisted the incidental bumps that happen around lawn tools and a compressor without chipping.

The two included keys are cut consistently, and both work smoothly. I strongly recommend storing the spare key offsite or in a separate lock box; it’s an inexpensive safeguard against lockouts. If you want an even smoother feel, a micro-shot of dry PTFE lubricant on the cam contact surfaces can reduce metal-on-metal scuffing.

What could be better

• Tolerance consistency: The initial “new lock” tightness is minor but noticeable. Pre-lubing with graphite helps, as does a short break-in period.
• Hardware confidence: I would love to see a slightly beefier retaining nut or a supplied lock washer. It’s a small addition that would reduce the temptation to overtighten.
• Documentation: The included instructions are adequate, but a quick diagram showing common cam orientations for different cabinet door alignments would help first-time installers.

None of these are deal-breakers. They’re small quality-of-life refinements that would elevate an already practical kit.

Practical tips for a clean install

• Match the cam orientation exactly to your original before tightening anything. A smartphone photo is your friend.
• Test with the door open. It’s safer and faster to spot misalignment before the cam can trap the door closed.
• Use graphite in the keyway and a dry lubricant on the cam’s contact surfaces; skip oils.
• Resist overtightening the retaining nut. If you’re concerned about vibration, threadlocker (medium strength) or a star washer is the right solution.
• Verify compatibility before purchase: flat key cam lock on a current Stack-On or Sentinel cabinet. If you have a tubular key or electronic dial, this isn’t a match.

Value and alternatives

For a direct-fit, same-day fix you can do with hand tools, this lock makes a lot of sense. Alternatives include sourcing an OEM replacement through the manufacturer or having a locksmith rekey or retrofit the existing lock—both viable, but typically slower or more expensive. If your cabinet is older with a tubular key system, you’ll need the correct tubular assembly or a locksmith conversion rather than this kit.

The Armstrong replacement lock aims at convenience and compatibility, and it hits that mark. It restores the cabinet’s intended function and looks good doing it.

Bottom line: my recommendation

I recommend the Armstrong replacement lock for anyone with a current Stack-On or Sentinel cabinet needing a straightforward lock replacement. It installs quickly, aligns well with existing hardware, and the brass finish brings a bit of polish without sacrificing practicality. Keep your expectations realistic—this is a like-for-like repair part, not an upgrade to vault-grade security—and take care not to overtighten the retaining nut during installation. With those caveats, it’s an easy, cost-effective way to get a cabinet back into safe, reliable service.