Officine Panerai’s rapid rise to manufacture status continues with its release of yet another in-house movement, Calibre P.5000, a manual-wound movement with an eight-day power reserve. The new caliber makes its debut in a pair of new watches, the Luminor Marina 8 Days and Luminor Marina 8 Days Oro Rosso.
While an eight-day power reserve is rare in wristwatches these days, it has been a part of Panerai’s history: the first watches that the brand created for Italian naval commandos had an eight-day power reserve, a requirement at the time for a unit that needed its timepieces to run reliably for long military operations. Between the end of the 1940s and early 1950s, Panerai, which originated in Florence, used a 16-ligne, manual-wound Angelus movement that met these criteria.
The structure of Panerai’s new Caliber P.5000 echoes those of movements from that era, in which the mechanism was contained between two plates, which concealed most of the wheels and allowed only a few details, such as the balance cock and intermediate wheel, to be visible. Here, the large plate, with brushed finish and diamond chamfering, conceals almost all of the mechanism, revealing only the variable inertia balance, which oscillates at a frequency of 21,600 vph (3 hz).
The movement is 35.7 mm (15 3/4 lignes) in diameter and 4.5 mm thick. It is made up of 127 parts, including 21 jewels. The variable inertia balance’s period of oscillation is adjusted by means of tiny timing screws on the outside of the balance wheel. In this system, the balance spring is free of the curb pins that would otherwise be used to modify its active length. The bridge supporting the balance is fixed by two screws; beneath the screws are threaded rings that turn in both directions to adjust the endshake of the balance staff pivots. This structure is intended to help the escapement keep running uninterrupted in case of shocks. Panerai uses two coupled spring barrels with toothed rims in series to achieve Caliber P.5000’s lengthy 192-hour (eight days) power reserve; this twin assembly enables the use of longer, thinner springs and hence, greater uniformity in delivering energy to the movement.
The timepieces in which Caliber P.5000 makes its debut are the Luminor Marina 8 Days 44mm, in an AISI 316L stainless steel case (Ref: PAM00510), and the Luminor Marina 8 Days 44mm Oro Rosso, in a 5N rose gold case (PAM00511; “Oro Rosso” is Italian for “rose gold”). Each model’s case has the familiar Luminor bridge device with locking lever to protect the winding crown, as well as the Panerai “sandwich” dial, composed of two superimposed disks with luminous material on the bottom layer shining through the stenciled numerals and indices of the top layer. The dial, which has large baton-shaped hour markers and a small seconds subdial at 9 o’clock, is black in the steel model and brown in the rose-gold version. The case, which has a 2.5-mm-thick corundum sapphire crystal over the dial, is water-resistant to 300 meters; the movement is visible through an exhibition caseback. Both watches come with an alligator leather strap with trapezoidal buckle that matches the case material, along with a second strap that can be swapped out with the included steel screwdriver. The Panerai Luminor Marina 8 Days 44mm is $7,300 in steel and $26,500 in rose gold.