Unknown 20mm

[Bruce]

I saw a 20mm sitting on a table at a store and they only wanted $6 for it so I bought it.
I have no clue what it is, the shell is gold/brass color and the projectile is grey with a small circular indent then there is a groove above that, going around the whole projectile.the headstamp reads

NECO 12 52 20mm.MK5. MOD.0

Any info is greatly appreciated

 

[orpheus72]

Bruce,

A picture would help a lot !

Seen the headstamp, i'm allmost sure its a 20x110USN dummy-round.

 

[zwerge]

I believe NECO is National Eastern Corporation.

 

[kahu1]

Sounds like a USN MK100 series 20mm, as id'd by Orpheus72.
Used mainly by the A-4 Skyhawk but also F-8 Crusader and a few others.
Some early ones used brass cases but later went to cad plated steel case.
Have seen nickeled brass cases as well, test it with a magnet.

cheers
Bob