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Combination Changes
Professional combo changes with proper change keys
S&G Mechanical Dial Locks
Opening instructions and professional service for Sargent & Greenleaf mechanical combination locks.
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Sargent & Greenleaf
Trusted by banks, government, and security professionals since 1857
How to Open an S&G Dial Lock
Standard 3-Number Dialing Procedure
⚠️ Before You Start
- Turn the dial slowly and smoothly
- If you go past a number, do NOT back up — start over from the beginning with 4 full left turns
- Don't force the handle — if it doesn't open, re-dial
- Standard S&G dials have numbers 0–99
Direction Reference
⬅️
LEFT (CCW)
Counter-clockwise
➡️
RIGHT (CW)
Clockwise
3-Number Combination (4-3-2-1)
Example Combination: 25 - 50 - 75
1st25
2nd50
3rd75
- Clear the lock: Turn the dial LEFT (CCW) at least 4 full turns to clear the lock
- First number: Continue turning LEFT and stop on the 1st number (25) on the 4th time you reach it
- Second number: Turn the dial RIGHT (CW), passing the 2nd number twice, then stop on it the 3rd time (50)
- Third number: Turn the dial LEFT (CCW), passing the 3rd number once, then stop on it the 2nd time (75)
- Open: Turn RIGHT slowly until the bolt retracts, then turn the handle to open the safe
✅ Quick Memory Aid (4-3-2-1)
Left 4× to 1st • Right 3× to 2nd • Left 2× to 3rd • Right 1× to open
💡 Be Precise
If you go past a number, do NOT back up. Start over from the beginning with 4 full left turns. Backing up will misalign the wheels.
4-Number Combination (5-4-3-2-1) — 4-Wheel Locks
Some S&G high-security locks use a 4-wheel pack with a 4-number combination. If your combination has 4 numbers, use this procedure:
Example Combination: 25 - 50 - 75 - 10
1st25
2nd50
3rd75
4th10
- Clear the lock: Turn the dial LEFT (CCW) at least 5 full turns to clear all 4 wheels
- First number: Continue turning LEFT and stop on the 1st number (25) on the 5th time you reach it
- Second number: Turn the dial RIGHT (CW), passing the 2nd number three times, then stop on it the 4th time (50)
- Third number: Turn the dial LEFT (CCW), passing the 3rd number twice, then stop on it the 3rd time (75)
- Fourth number: Turn the dial RIGHT (CW), passing the 4th number once, then stop on it the 2nd time (10)
- Open: Turn LEFT slowly until the bolt retracts, then turn the handle to open the safe
💡 How Do I Know If I Have a 4-Wheel Lock?
If your combination has 4 numbers instead of 3, you have a 4-wheel lock. These are typically found on S&G Group 1 locks, GSA containers, and government-spec safes (R6700 series, 2740B).
S&G Lock Models
Group 2 Locks Standard Security
20-minute manipulation resistance • Commercial grade
Most common on home safes, gun safes, and commercial safes. Models include:
- 6730 - Standard spy-proof dial
- 6741 - Front-reading dial
- 8400/8500 Series - Key-locking dials
Group 1 Locks High Security
UL Listed • Manipulation resistant
Required for GSA containers and high-security applications:
- R6700 Series - Government spec
- 2740B - High security
- 8077 - Key-operated
Changing the Combination
⚠️ Professional Service Required
- S&G mechanical locks require special change keys
- Incorrect procedure can lock you out permanently
- We recommend professional combination changes
Unlike electronic locks, mechanical S&G locks require a change key specific to the lock model. The change key is inserted while the lock is open, and a precise procedure must be followed.
Our S&G Lock Services
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Safe Opening
Lost combo? We can open your safe without damage
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Lock Repair
Sticky dials, worn parts, internal repairs
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Electronic Upgrade
Convert dial to S&G electronic lock
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Won't open with correct combo | Dialing too fast | Slow down, re-dial carefully |
| Dial feels gritty | Dust/debris inside | Needs cleaning/service |
| Dial spins freely | Broken drive cam | Professional repair needed |
| Bolt won't retract | Bolt work issue | Don't force - call for service |
| Forgot combination | N/A | Professional safe opening |
Need S&G Lock Service?
Professional combination changes, safe opening, and repairs.
📞 (321) 224-5625