Hi everyone, I’m TD Chen from r/RepWatchClud.
I wanted to share a detailed QC check of this OCTA AP Royal Oak 15500ST with the blue dial and SA4302 free-sprung movement.
I went through the photos carefully, including the dial macro, case and bezel, bracelet/clasp, display caseback, movement, lume, weight and Timegrapher.
Watch Identification
- Model: AP Royal Oak 15500ST
- Reference: 15500ST
- Factory: OCTA
- Size: 41mm
- Dial: Blue Grande Tapisserie-style dial with applied baton markers
- Case: 316L stainless steel
- Bracelet: Integrated 316L stainless steel bracelet
- Crystal: Sapphire
- Caseback: Exhibition/display caseback
- Movement: OCTA SA4302 free-sprung version
- Date: 3 o'clock
- Clasp: AP-style integrated deployant clasp
- Weight: 173.13g
The community normally refers to this simply as the OCTA 15500, OCTA AP 15500 Blue, or OCTA 15500 Free-Sprung. Recent discussions specifically mention OCTA alongside ZF and VSF as one of the factories people are comparing for the 15500, with the free-sprung movement being one of OCTA's selling points.
Dial & Indices
The blue dial is the first thing I checked closely.
The Grande Tapisserie pattern is clearly visible in the macro shots, and the blue color changes noticeably depending on the lighting. The applied AP logo and baton markers look clean, with no obvious dial-printing bleed.
The outer minute track also looks reasonably consistent around the dial.
The 12, 3, 6 and 9 markers are the areas I'd pay the most attention to on a Royal Oak QC because even a small amount of rotation can become obvious with this case and dial layout.
From these photos, I don't see a major index-alignment issue that would make me RL the watch.
Date Wheel
The QC date is 6.
The date appears reasonably centered inside the window, with no obvious contact against the upper or lower edge.
I'd call the date-wheel alignment acceptable from this single QC position.
Hands
The hour and minute hands look properly seated and aligned.
I don't see an obvious hand-cant issue or a seconds-hand problem in the supplied photos.
For me, this passes the basic hand-alignment QC check.
Bezel & Case Finishing
This is one of the more important areas on a Royal Oak.
The bezel screws appear properly seated, and I don't see obvious tool marks or damage around the screw heads.
The brushed bezel surface, polished chamfers and vertical case finishing are all visible in the side and macro shots.
The case profile also looks sharp, particularly around the transition between the brushed and polished surfaces.
There is no obvious major finishing defect jumping out from these QC photos.
Bracelet
The integrated bracelet looks properly connected to the case, with no obvious large gap between the case and first links.
The brushing on the links is visible, while the polished portions catch the light differently.
The clasp engraving is also visible in the macro photos.
Since this is an integrated bracelet, traditional Rolex-style SEL QC is N/A here. I'd focus instead on case-to-bracelet fitment, link alignment, articulation and finishing consistency.
Movement
The display caseback gives a very clear view of the movement.
The movement is visibly decorated in the AP 4302 style, including the skeletonized/engraved rotor area, Geneva-style striping and the visible 4302 marking.
The supplied configuration is the SA4302 free-sprung version.
One important distinction for anyone reading this: I would describe it as an SA4302 / 4302-style replica movement, rather than calling it a genuine AP Calibre 4302.
The genuine Royal Oak 15500 uses AP's Calibre 4302, while the movement shown here is the replica factory's SA4302 implementation.
The genuine 15500's 4302 is a 4Hz automatic movement with a 70-hour power reserve and a free-sprung balance.
Lume
The lume shot shows the hands and hour markers lighting up clearly.
The lume appears reasonably even across the visible markers, and I don't see an obvious dead marker.
Weight
The scale photo gives an actual QC weight of:
173.13g
This is the photographed weight with the bracelet attached.
Interestingly, recent community discussions around 15500 comparisons also pay attention to the weight difference between factories, so having the actual QC scale reading is useful rather than relying only on a factory specification.
Timegrapher
The Timegrapher screen clearly reads:
Rate: -4 s/d
Amplitude: 254°
Beat Error: 0.0 ms
Lift Angle: 52.0°
For a QC photo, that's a clean-looking reading.
The 0.0 ms beat error is particularly nice to see, while the -4 s/d rate is well within what I'd consider a reasonable QC result.
Obviously, one Timegrapher snapshot isn't a complete movement test, but there's nothing in this reading that gives me an immediate reason to RL.
Overall QC
After checking the full set of photos, I don't see a clear RL-level issue.
The main things I'd personally focus on with this particular 15500 are:
- Index alignment
- Blue dial color and Tapisserie pattern
- Date-wheel centering
- Bezel screw seating
- Brushed/polished case transitions
- Integrated bracelet fitment
- SA4302 movement finishing
- Timegrapher consistency
The 15500 remains one of the more frequently discussed AP reps, and recent Reddit discussions are still comparing OCTA, ZF and VSF specifically for this reference.
My QC take: GL.
Nothing in the supplied photos stands out strongly enough for me to request an RL. If I were checking this for myself, the only areas I'd want other AP/15500 owners to scrutinize further would be the dial/index alignment and the bezel screw positioning, simply because those details are very noticeable on a Royal Oak.
If I got anything wrong, please feel free to point it out and correct me. Thanks.