Hannah can you tell us a little on Swiss Lugers?
The Luger was first adopted by the Swiss Army in 1900 and bore the Swiss Cross in Sunburst over the chamber, and the DWM logo on the toggle link. These were produced by the German company DWM in 7.65mm (.30 Luger).
In 1906, Switzerland was informed that upgrades had been made to the original design, and that the flat mainspring had been replaced by a coil mainspring. These models are referred to as 1900/06.
10,215 units were ordered, and at some unspecified time, the Cross in Sunburst was altered to the Cross in Shield mark, still with the DWM mark on the toggles.
Prototype high cap mags and shoulder stocks were soon developed in Switzerland for this model.
In 1914, WW1 caused problems with deliveries of Lugers to Switzerland, as most were diverted to German Army use.
By war's end, 1918, Waffenfabrik Bern, the Swiss arsenal manufacturers had tooled up for domestic Swiss Luger production.
Changes were largely cosmetic, but included the substitution of the "Waffenfabrik Bern" logo in place of the DWM scroll, an uncheckered border on the walnut grips, and a slight thickening of the leading edge of the sideplate.
In 1929, in an attempt to cut costs of production, the 06/29 model was developed.
Many differences are visible, among them:
Straightening of the forward gripstrap,
Grips and mag bottoms made from plastic,
Eliminating machining steps by leaving a "step" in the receiver ring,
Deleting knurling from toggle knobs, takedown lever, and mag release button,
Redesign of grip safety lever, and interior of sideplate,
Simplification of thumb safety lever,
Slight redesign of firing pin and breech block,
Issuing only 2, instead of 3 spare mags per pistol.
S.I.G. at Neuhausen produced the lower frame, upper receiver, and toggle link. All other parts continued to be made at Waffenfabrik Bern.
Adoption of this gun was in 1929, but deliveries didn't start till 1933.
The 06/29 *looks* very different from other Lugers, because of it's odd straight foregrip, and is easily distinguished.
There are many volumes written about Swiss Lugers and a lot more detail than I can go into here, but this should give you the basics.
The Luger in your picture is a 1900/06.