On dutch soil many shrapnell parts of other shells and grenades can be found. Some are very small, indicating possible hand grenade parts. Others are inner shell parts which can only be identified with knowledge of that particular shell. Below a sample of several other, unidentified, parts.

British fighterbomber air-to-ground canon ammo

20mm Hispano canon rounds were used by many allied fighterbombers - including models of the Typhoon, Spitfire, Hurricane etc. and also by bombers like the Shackleton. The spent cartridges were discarded in flight. Therefore these can litterally be found anywhere, not just on battlefields. Of course higher concentrations can be found on battlefield were these aircraft gave ground support.

20mm round cases are fairly big. The headstamps can't be more clear: '20mm' is stamped on it - together with the production facility and production date. Some of the headstamps I found in Holland:

Recommended reference: Headstamps – Military Cartridges

Allied small arms calibres

Battlefields on Dutch soil are littered with small arms calibre cases. The battlefields which I searched were mainly Canadian and Polish forces fighting the Germans. Cases and rounds of specific types of weapons can be found here.

All commonwealth forces used British weaponry as their backbone. This means traces of those weapons can be found. Enfield rifles (.303), Bren machineguns (.303), Sten guns (9mm) and British tank Besa machineguns (7.92mm) are common. .50 cal cases can also be found although these are most likely allied fighterbomber and bomber spent cases.

Headstamps of allied rounds contains a lot of information. The battlefield which I searched have been battled by Canadian and Polish divisions. The Canadians had some home made ammo - of course the Polish did not. Both used mainly British manufactured ammo. The British and commonwealth forces used mostly rimmed riffle cases. The rimless cases were used by tanks of British origin like the Churchill. The photographs below picture a comparison between the rimmed and rimless cases (3rd photo) and a comparisson between elongated primer dots (Bren gun) and round primer dot (Enfield rifle) (4th photo).

Headstamps

The list below contains found cartridges; some have been found in larger quantities. Many other have been found which are unreadable. Different types of weapons can be identified by these cartridges: .303 Enfield rifle, .303 Bren LMG, 9mm Stengun, 50 cal cases (aircraft, since these are found only single pieces), 7.92mm Besa British tank machineguns and 30-06 from the M1 Garand used by US troops (found on other battlefields). 

*.303 bullet types: W = armour piercing, VII and IIZ are normal 'ball' types. GIZ = tracer.

*the 3AH Percussion Tube is something much different. These were used as igniters for several breech loading artillery guns. This specific tube was used for the 4.5" Gun, 5.5" Gun and 7.2" Howitzer. The tube itself as seen below is complete - it had no bullet. At the end the primer firing holes are visible, which would ignite the initial gun/ howitzer gunpowder from the breech. The tube has 3 small dents in the lower area which were holding an inner gas seal in place.

*50 cal casings were discarded in flight by bombers/ fighter bombers. If these are found in large concentrated quantities it is presumable these were used by ground based equipment (tanks/ halftracks). I always found single ones - which are most likely used by air combat actions. All headstamps are manufactured by US factories. (note the SL headstamp year mismatch: it was stamped twice with '42'!)

Britsh manufactured Mortar grenades leave also sometimes beside shrapnell tail fins  to find - as can be seen below. The tails with 2 holes are the ML 3inch mortar type, the tail with 3 holes are the ML 4.2 inch mortar type. From both types a reference photograph is depicted.

I also stumbled upon a live fuze (Mk.152) for the ML 3 inch mortar grenade. This one was still in its original protective casing, 'Remove before firing' can still be read. The drawing is a reference for the resembling Mk.162 fuze.