All this means that the Caliber 400 is highly resistant to magnetism it has been, says Oris, stress-tested to 2,250 gauss. The movement, despite not using a silicon balance spring, has a total of 30 parts made of amagnetic materials, including the lever and escape wheel, as well as the axes of a number of critical components including the balance, escape wheel, and lever. This efficiency is enhanced by the use of a silicon lever and escape wheel, which interact with very low friction and which, of course, do not require lubrication (in this movement and others using the same solution, this contributes to better long term rate stability). Oris says that the Caliber 400 delivers about 85% of the mainspring barrel torque, as opposed to an average of 70% in a conventional movement. Power is delivered in the caliber 400 by two mainspring barrels, and the design of the gear train – including the gear teeth profiles, as well as that of the escapement – is intended to minimize energy losses due to friction and optimize efficiency. As a consequence of the cost and time it takes, series-produced in-house movements are generally made by companies that are either part of a larger group, with a big war chest, or by individual companies with the resources (and money) that it takes to do it. All this is by way of saying that today's announcement from Oris, of its new Caliber 400 self-winding, five-day, antimagnetic movement, is a big deal for the company and its fans. Many so-called new movements are, in fact, variations on existing movements, and developing an entirely new in-house caliber is an expense that can easily take years and run into the millions of dollars (or yen, or francs, or euros, depending on where you've set up shop). The movement, for all that it is often the least talked-about part of a watch, is of course what makes a watch a watch, and they're extremely expensive to develop and to tool up to produce. It is not often that manufacturers announce a new movement, and as most know, there are excellent reasons for this.

Oris calibre 400 issues