Sentry Safe Dial Lock Instructions

Opening instructions for Sentry Safe mechanical dial combination locks.

S6770
S8771
SFW123DTB
Combo Fire Safes

⚠️ CAUTION — Read Before Working on Your Sentry Safe

Always open the safe first and keep the door open while practicing your combination. Test that you can open the lock at least 3 times with the door open before closing it.
Sentry Safes are NOT repairable once drilled. Unlike commercial-grade safes, most Sentry Safe models cannot be re-locked or repaired after a locksmith drills them. The safe body is typically destroyed in the process and must be replaced entirely.
Lockout cost: $150–$400 depending on the model. A basic Sentry fire safe can cost $150–$200 to drill open, while larger or more secure models can run $300–$400+. Since the safe can't be repaired after drilling, you'll also need to buy a new safe.
Do not force the handle or pry the door. Sentry Safes have anti-pry features and relocker mechanisms. Forcing the door can trigger the relocker, making the safe significantly more expensive to open.

About Sentry Safe Dial Locks

Many Sentry Safe models come with a traditional mechanical dial combination lock. These dials use the standard 3-number combination with a 4-3-2-1 dialing sequence — the same procedure used on S&G, LaGard, and Mosler dial locks. Sentry dial locks are simple and reliable, but the combination cannot be changed by the user — only a professional locksmith with the correct change key can change the combination.

Brand	Sentry Safe (Master Lock Company)
Common Models	S6770, S8771, SFW123DTB, SFW082, Combination Fire Safes
Combination	3 numbers (3-2-1 dialing pattern: left-right-left)
Dial Range	0–99
Power	None (fully mechanical)
Code Change	Professional locksmith required — NOT a DIY procedure

How to Open a Sentry Safe Dial Lock

Sentry Safe 3-Number Dialing Procedure (3-2-1)

Turn the dial LEFT (counterclockwise) 3 times, stopping on your FIRST number on the 3rd time you reach it.
Turn the dial RIGHT (clockwise) 2 times, stopping on your SECOND number on the 2nd time you reach it.
Turn the dial LEFT (counterclockwise) and stop directly on your THIRD number.
Turn the handle to open the safe.

⚠️ Be precise — if you go past a number, do NOT back up. Start over from the beginning with 3 full left turns.

Dialing Tips for Sentry Safes

Always start by turning LEFT 3 full revolutions to completely clear the wheels.
Sentry dial locks tend to have looser tolerances than commercial-grade S&G or LaGard dials. If the combo doesn’t work on the exact number, try ±1 on each number.
Turn the dial slowly, especially near each target number.
If you overshoot a number, even by one tick mark, start the entire sequence over.
Do NOT apply pressure to the safe handle while dialing the combination.
The dial should turn smoothly. If it feels gritty, stiff, or jams, the lock may need service.

Changing the Combination

⚠️ Professional Locksmith Required

Sentry Safe dial locks cannot be reprogrammed by the user. Changing the combination requires a professional locksmith with the correct change key for your lock model. The change key is inserted into the back of the lock (inside the safe door) while following a precise dialing sequence.

Do not attempt to change the combination yourself. Incorrect procedures can permanently disable the lock, requiring drilling — and Sentry Safes cannot be repaired after drilling.

Common Issues

Combination doesn’t work: Dial more slowly and precisely. Make sure you’re going the correct direction (Left-Right-Left) and counting pass-throughs correctly. Try ±1 on each number.
Dial feels loose or wobbly: The set screw on the dial ring may be loose, or the dial may need to be re-seated on the spindle. A locksmith can fix this quickly.
Handle won’t turn after correct combination: The bolt work may be jammed or the relocker may have engaged. Do NOT force it — call a professional.
Forgot combination: Try the combination printed on the card that came with your safe. If you’ve lost it, contact Sentry Safe customer service with your model and serial number — they may be able to recover it. Otherwise, a locksmith will need to drill the safe.
Dial spins freely: The drive cam or spindle inside the lock is broken. Professional repair or drilling is required.

Before You Call for Drilling Service

⚠️ Try These Steps First — Drilling Destroys the Safe

Sentry Safes cannot be repaired after drilling. Cost ranges from $150–$400 depending on the model, plus the cost of a new safe. Before calling a locksmith to drill, try:

Try the combination from the original combo card that came with the safe
The key on Sentry dial safes is for unlocking the handle only — it does not bypass the dial combination
Dial more slowly — try ±1 on each number of your combination
Contact Sentry Safe customer service at 1-800-528-9922 for combo recovery
Visit sentrysafe.com/support/lost-key-combo

Manufacturer Contact

📄 Sentry Safe Customer Support

Phone: 1-800-528-9922
Website: sentrysafe.com/support
Lost key/combo: sentrysafe.com/support/lost-key-combo

Frequently Asked Questions

Can I change the combination on my Sentry Safe dial lock myself?

No. Sentry Safe dial locks require a professional locksmith with a special change key to change the combination. This is not a do-it-yourself procedure. Attempting to change it without the proper tools can permanently damage the lock.

How much does it cost to drill open a Sentry Safe?

Typically $150–$400 depending on the model and your location. Keep in mind the safe cannot be repaired after drilling — you’ll need to purchase a replacement safe as well.

Can a Sentry Safe be repaired after it’s drilled?

No. Unlike commercial safes from brands like AMSEC or Gardall, Sentry Safes use lightweight composite construction that cannot be re-locked or welded shut after drilling. The safe must be replaced.

I forgot my Sentry Safe combination. What should I do?

First, check for the original combination card that came with your safe. Next, try the override key. If neither works, contact Sentry Safe customer service at 1-800-528-9922 with your model and serial number — they may be able to recover your combination. Drilling should be the last resort since it destroys the safe.