Comparison
Hamilton Khaki Field Mechanical vs Automatic
Published
Short answer
Both are 38mm Khaki Field watches with an 80-hour power reserve, sapphire and Super-LumiNova. The Mechanical uses the hand-wound H-50, is rated 50m and costs less; the Automatic uses the self-winding H-10 and is rated 100m. Pick the Mechanical if you enjoy winding a watch and want the purest vintage field watch; pick the Automatic if you want it to wind itself and handle swimming.
Hamilton
Hamilton Khaki Field Mechanical 38mm, hand-wound
See price on Amazon
Hamilton
Hamilton Khaki Field Auto 38mm, H-10, 100 m
See price on Amazon
Hamilton
Hamilton Khaki Field Auto 42mm on bracelet
See price on Amazon
- Hamilton Khaki Field Mechanical 38mm, hand-wound
- Case size
- 38 mm
- Movement
- H-50 hand-wound
- Power reserve
- 80 hours
- Water resistance
- 50 m
- Hamilton Khaki Field Auto 38mm, H-10, 100 m
- Case size
- 38 mm
- Movement
- Swiss H-10 automatic
- Power reserve
- 80 hours
- Water resistance
- 100 m
- Hamilton Khaki Field Auto 42mm on bracelet
- Case size
- 42 mm
- Movement
- Swiss H-10 automatic
- Power reserve
- 80 hours
- Water resistance
- 100 m
| Pick | Case size | Movement | Power reserve | Water resistance | Price | Link |
|---|---|---|---|---|---|---|
| Hamilton Khaki Field Mechanical 38mm, hand-wound | 38 mm | H-50 hand-wound | 80 hours | 50 m | - | Amazon |
| Hamilton Khaki Field Auto 38mm, H-10, 100 m | 38 mm | Swiss H-10 automatic | 80 hours | 100 m | - | Amazon |
| Hamilton Khaki Field Auto 42mm on bracelet | 42 mm | Swiss H-10 automatic | 80 hours | 100 m | - | Amazon |
Facts are taken from each Amazon listing. Prices are checked daily and shown with their date.
Verdict
Buy the Khaki Field Mechanical if you like the daily winding ritual, want the most traditional field watch and will not swim with it. Buy the Khaki Field Automatic 38mm if you want a self-winding everyday watch with 100m water resistance, or the 42mm Automatic if you have a larger wrist.
The Hamilton Khaki Field is one of the most recommended field watches, and the 38mm version comes in two movement types: the hand-wound Khaki Field Mechanical and the self-winding Khaki Field Automatic. This page is for buyers deciding between them. It compares the two Amazon listings line by line, explains what hand winding is like day to day, covers thickness and the case back view, and points out what the listings do not confirm. It also mentions the 42mm Automatic for larger wrists.
Spec comparison from the listings
Both listings describe a 38mm stainless steel case with a black dial, sapphire crystal and Super-LumiNova, and both give an 80-hour reserve. The real differences are the movement, the water rating, the strap supplied in each listing and the price. Neither listing gives case thickness or lug to lug, so those are marked as not confirmed.
| Khaki Field Mechanical 38mm | Khaki Field Automatic 38mm | |
|---|---|---|
| Movement | H-50, manual winding | Swiss H-10, automatic |
| Power reserve | 80 hours | 80 hours |
| Water resistance | 50m (5 bar) | 100m (10 bar) |
| Case | 38mm stainless steel | 38mm stainless steel |
| Crystal | Sapphire | Sapphire |
| Lume | Super-LumiNova | Super-LumiNova |
| Strap in this listing | Textile, pin buckle | Leather, pin buckle |
| Thickness | Not confirmed in listing | Not confirmed in listing |
| Lug to lug | Not confirmed in listing | Not confirmed in listing |
| Listed price | $675.00 | $795.00 |
H-50 vs H-10: what the movement changes
The H-50 in the Mechanical has no rotor. You wind it by turning the crown until it stops, and it then runs for up to 80 hours according to the listing. Most owners give it a wind every morning or every other morning, which takes a few seconds. The H-10 in the Automatic has a rotor that winds the mainspring as you move, so if you wear it daily it simply keeps running.
The 80-hour reserve on both is long for this price. It means either watch can sit for a weekend and usually still be running. That makes the Mechanical easier to live with than older hand-wound watches with short reserves, because a missed wind is not a problem. For background, read automatic vs manual wind watches and power reserve explained.
- Wrist motionYour arm moves.
- RotorA half-moon weight spins on its axle.
- Reversing wheelsTurn both swing directions into winding.
- Mainspring barrelStores the energy as a coiled spring.
- Gear trainCarries the power to the hands.
- Escape wheelReleased one tooth at a time.
- Pallet forkLocks and unlocks the escape wheel.
- Balance wheelSwings back and forth at a steady rate.
Water resistance: 50m vs 100m
The Automatic's listed 100m (10 bar) is commonly considered fine for swimming and snorkeling, though not scuba. The Mechanical's 50m (5 bar) is generally treated as suitable for rain, hand washing and brief light swimming only. If you want a field watch you never take off at the beach or pool, that gap favors the Automatic.
Remember that the rating is a test pressure, not a safe depth, and seals age over time. Have water resistance checked at each service. The water resistance decoder shows what each rating usually covers.
Note.Never pull out or turn the crown while the watch is wet or underwater, especially on a hand-wound watch that you wind often.
Thickness, feel and the vintage look
A hand-wound movement has no rotor stacked on top, so manual watches are often a little slimmer than automatic versions of the same design. The two Hamilton listings do not give thickness figures, so check Hamilton's own spec page if the exact number matters to you. Either way, both are 38mm field watches that sit low compared with most divers.
The Mechanical is closer to the original military field watches, which were hand-wound, and it comes on a textile strap in this listing. The Automatic in this listing comes on leather. Both have standard lugs, so swapping straps is easy. For more field watch picks, see the best field watches.
What about the 42mm Automatic?
Hamilton also lists the Khaki Field Automatic in 42mm with the same H-10, 80-hour reserve, 100m rating and sapphire, on a stainless steel bracelet with a folding clasp in that listing, at $845.00. There is no 42mm Mechanical in our listings. If your wrist is over about 7 inches, compare sizes in Hamilton Khaki Field 38mm vs 42mm before choosing.
The choice between Mechanical and Automatic is really a choice about habits, so it helps to be honest about how you wear watches. If your watch goes on every morning and comes off every night, either one works. If you often leave it in a drawer for a week, both will stop, and you will need to wind and set either one. In that case a single watch winder can keep the Automatic running, but it will do nothing for the hand-wound Mechanical.
Frequently asked questions
Do I have to wind the Khaki Field Mechanical every day? Not strictly. The listing gives an 80-hour reserve, so a full wind lasts more than three days. Most owners wind it daily as a habit so it never stops.
Can I wind the Khaki Field Automatic by hand? The listing does not state it. Many modern automatics can be wound by the crown, but check Hamilton's manual for the H-10 before relying on it. See how to wind an automatic watch.
Which is more accurate? Neither listing gives an accuracy figure. Accuracy depends on regulation more than winding type. See how accurate should an automatic watch be.
Is the Mechanical or the Automatic better value? The Mechanical has the lower listed price and the same 80-hour reserve. The Automatic costs more but adds self-winding and double the water resistance.
What you need for this
- See price on AmazonAmazon
Hamilton Khaki Field Auto 38mm, H-10, 100 m
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