Diana Model-30 Military Trainer - 10/1939.
Here are some pics of a decent example of a 1930s mod 30 military trainer, dated 10,39.
The first thing that strikes you when you hold one of these rifles is how dainty it is. Its length, 42 inches (107cm), isn't especially petite but the cylinder is narrow and the rifle is suprisingly light.
The second thing you notice is the high quality of the detailing. The rearsight is the block and element type, also found on the model 26 underlever. The front sight has a ramp that is nicely grooved, to reduce glare, and is extremely solidly made. The front sling band is made of incredibly thick, blued steel and the short cocking lever is solid steel.
In terms of the build quailty and detailing, it's quite similar to the Haenel 33 Junior, which it was in competition with at the time. Perhaps the presence of the other encouraged these companies to "raise their game" rather than build down to a price, which must have been tempting.
I haven't done a velocity check or taken a look inside the cylinder yet, but looking at the small swept volume I would imagine that even operating at its maximum potential this is a low-powered rifle. No doubt it would have seemed very impressive to a (Hitler?!) youth on the parade ground, but as a serious military firearms trainer it can't have been much of a performer.
Here are some partial stripdown pics:
Diana Model-30 (taken to US in wartime)
Spotted by Steve on Gunbroker. This is the blurb:
"WWII captured Diana Model 30 (SportModell)air rifle made it the style of of a K98k Mauser. 8-1939 dated on the butt stock. It shoots 4.4mm Diabolokugel(pellets, not bb balls). I got it out of the safe and cocked it and it sounds strong when fired. All functions seem to work. I acquired it over 20 years ago from my retired co-worker that originally liberated it(Some of his personal items are in the first picture for context). My friend was in a maintenance battalion and therefore took his English motorcycle with the rest of the equipment to France within 2 weeks of D-Day(he had the special mimeograph copy of Yank printed the first week in France). At some point he went exploring the countryside and vacated German emplacements in the forests. He found a building in a small town, packed full of guns confiscated by the Germans. He said he had to climb over stacks 3 and 4 feet high and couldn't walk on the floor of the place. He grabbed this rifle and one other because that's all he could carry. He went back to base and commandeered a jeep. By the time he made it back it was already off-limits with MPs guards. I have tried to show the great condition (and any imperfections)of this rifle. Considering it has gone through a World War, it is is very nice functional condition. Shipping will be $25.00."