Miyota Caliber 8315

Miyota caliber 8315

Miyota Caliber 8315 Wide

Manufacturer Miyota (Citizen)
Caliber Number 8315
Movement Type Automatic, self-winding mechanical
Lignes
11.5”’
Diameter 26mm
Height 5.67mm
Jewels 21
Beat Rate
21,600 bph, 3 Hz
Lift Angle
49 degrees
Accuracy
See below…
Power Reserve
60 hours
Rotor Winding Direction Counterclockwise
Hand Windable?
Yes
Stem 065-212 (tap 10)
Dial Screws 929-610
Case Clamps
082-060
Case Clamp Screws
924-460
Anti-Shock System Parashock
Hand Sizes
1.50mm / 1.0mm / 0.17mm
Functions Central hours; central minutes; central sweeping seconds; date calendar at 3:00
Hacking Seconds?
Yes
Quickset Date?
Yes
Finishing
“Fine finishing” decoration on the barrel bridge; blued screws on the oscillating weight, barrel bridge, and balance cock
Country of Manufacture Japan
Known Models (Add your watch in the comments below…)

The Miyota caliber 8315 is a 21 jewels automatic movement, made in Japan. It is part of Miyota’s line of “Standard Automatic” watch movements, but what sets this calibre apart from the others is that is has a longer running time with more than 60 hours power reserve. Miyota states that this is their longest running mechanical movement.

Some of the topics covered in this caliber listing:

Accuracy:

Miyota claims that the cal. 8315 has an average accuracy rating of -20 / +40 seconds per day in normal operating conditions.

Time and Date Setting:

As a basic 3-hander with a date, setting the 8315 is straightforward. There are 3 crown positions:

  1. Crown against the case – Manual winding: full power serve is reached when the crown is turned at least 51 times. You cannot over-wind the movement.
  2. Crown pulled out one click – Date setting mode: turning the crown counterclockwise will advance the calendar datewheel. Do not make this adjustment when the hands are between the hours of 9:00pm and 1:00am.
  3. Crown pulled out two clicks – Time setting mode: rotate the crown to set the time of the hands. The seconds hand will be hacked in this mode (aka stopped for precise time-setting).

Replacement Prices:

At the time of this post, replacement pricing for the Miyota 8315 was found online in the range of $85 to $89.95 USD. When ordering bulk from Miyota, the minimum order quantity is 100 pieces.

Compatibility:

The 8315 is based on the 8200 series framework. Therefore, it is compatible with most caliber 82XX dials, hands, and cases (such as the popular Miyota 8215).

Additional Resources:

You are reading Caliber Corner, the world's most popular resource for watch movement pics, specs, mods and DIY repairs. Follow @calibercorner on Twitter, Instagram but NOT Facebook. Subscribe on YouTube. Join our mission to spread movement awareness!

Join the discussion on Miyota caliber 8315?

  • Keep comments respectful and follow our community guidelines.
  • Keep comments on the topic of Miyota caliber 8315

For off topic or general watch questions, post in the Caliber Corner Forum.

guest

9 Comments
oldest
newest most voted
Inline Feedbacks
View all comments
HoustonReal
HoustonReal
2 years ago

The Miyota 8315 replaces the 821A. It is a hacking and decorated version or the Miyota 8215, that has now been upgraded with a new mainspring. The power reserve is now a minimum of 60 hours, and the movement is offered in silver and gilt versions.

Diameter: 11.5 Ligne/25.6mm
Height: 5.67mm
Jewels: 21
Complications: Date
Power Reserve: 60+ hours
Lift Angle: 51
Antishock: Parashock
Hand Sizes: 100/152/17
Dial Feet: 25/50

miyota_8315_movementback.jpg
Miyota_8315.jpg
John le Carré
John le Carré
1 year ago
Reply to  HoustonReal

Very good and accurate text, @HoustonReal, lift angle is 51° – 53° though. Just helping here.

William Shatner
William Shatner
1 year ago

@CC, I’ve measured my 8315’s lift-angle too. My Witschi-apparatus ensures me of the correct lift-angle of 52° (degrees).

John le Carré is thus fairly right though. Witschi is the correct Swiss measuring device, since a very long time, since I can remember anyways. No hard feelings, @CC.

Zdeněk Bartoš
Zdeněk Bartoš
2 months ago

It is 49, not 51, not 52, not 53. This site says 49. Miyota says 49. You are saying wrong lift angle and I first got the bad reading because setting was wrong. Now I get the good reading because I use the right setting at 49.

miyota-8315-lift-angles
Don B
Don B
1 year ago
Reply to  HoustonReal

It appears to be a descent movement. I just installed one in my Bulova Devel Diver 666, replacing to 8215 that they use from the factory. I really prefer the hacking function and the stock movement was just not doing it for me. The 8315 is a direct drop in movement and no mods were required. My unit is currently at +2 seconds with no beat error. I will run it for a couple weeks and then recheck. The hacking is instant and easy to accomplish. Setting appears to be the same slightly loose feel that you get with the… Read more »

Redbeard914
Member
1 month ago
Reply to  Don B

Where were you able to find an 8315?

William Shatner
William Shatner
1 year ago
Reply to  HoustonReal

HoustonReal, you’re spot-on ( what’s a 1° deviation in your and my measurements (?) – it’s close enough, ey ?! 😉 )

I too find it a feisty little 8315-caliber. Another big win for Citizen ánd Miyota alike.

cybertrancer
Member
2 months ago

Hi! I have a Laco “BIELEFELD 42” configured with this movement (they call it Caliber 31). It has 69 hours of power reserve (until it stops), measured a few times in the last 2 months. During normal daily wear, it runs about +2s a day. It has the “hacking” feature when setting the time. Another great movement by Miyota.

Seagull Caliber St19

Join our mission to spread movement awareness!

Members Online

  • keepthetime

Recent Forum Posts

Sponsors

9
0
Would love your thoughts, please comment.x
()
x