The first cartridge, at first glance, appears to be a 303 but the FNM code suggests it was made at Fabrica Nacional de Municoes e Armas Legeiras, Moscavide, Portugal. This would lead me to think it's actually a 7.7 x 56R cartridge which was interchangable with 303's anyway. The number is the year of manufacture 51 = 1951.
The second cartridge looks like a .50cal but the lettering I am not sure of as it appears to be in a 'none-English' alphabet The 75 will again be the year of manufacture.
The third one is easy. .50cal drill round, Frankford Arsenal, USA, 1944. These are quite common.
Last one is outside of my area of expertise as it is post 1945 but the markings suggest it's a 30mm cannon cartridge, with the PRAC denoting it as a practice round. The 90 will be the date, the 173a probably a batch number and the CY the manufacturer......but you'd need an expert in this field to confirm this.
I would suggest that the last one is a 30mm Aden cannon round. I owned a couple of these some years ago. Purely guessing but maybe the second one is a 1975 dated Soviet Bloc 12.7mm round - their equivalent to the .50 I had a few of these knocking around from a mate who lived in Hereford and had brought them home as a souvenir. Long since disposed of them so I can't state for certain what the markings were though.
Thank you for all your info guys although im now confused on the aden cannon round. i forgot to mention that i am a complete novice with this stuff and im looking for info on them as im hoping to give them as a gift to my dad for x mas (unusual presant choice i know but at least he wont be expecting it and anythings better then socks) would this be a cannon on a plane? also, all the rounds look like they have been "made safe" one way or the other apart from the first one shown on the pictures supplied is there a way of telling if its been deactivated or whatever?
Yes....they're all perfectly safe. The 303 (or 7.7 whichever you prefer ) has a firing pin mark on the blast cap on the base, showing it has been fired and then put back together again. It can't be fired again without replacing the blast cap and refilling with propellant charge. Same goes for your Israeli round.
The .50cal drill round has bloody great holes drilled in it to is perfectly safe. It also has NO blast cap.
The Aden round is denoted practice so will also be safe but wait for one of the experts on these rounds to confirm it. I'd hate for you to find out the hard way that the inert cartridge has been topped with a live projectile !
Its hard to tell with the ADEN round if it has a live cap as it is electrically initiated and has no mark as such. There could be a score mark where the firing contact pin has scratched the surface but the same mark is found on live rounds which have been unloaded as they have to pass through the chamber to unload the gun.
This is a ADEN cannon, this one is from a BAe Hawk 200, its the only British aircraft to still use it as the Tornado and Typhoon use 2 diffrent versions of the Mauser BK27mm.
Oh, forgot to mention the Practice round projectile has no Ex content at all, its just a lump of steel and it has been fired as I can see the drive band with rifling grooves has been forced into the case. If you pull the round out of the case, the drive band should sit on top of the case not in it.