Going thru and old stash of ammo this morning and found a box of Geco 9MM Luger Parabellum. It was a 50 round box but only has 45 left in it. Not sure where I picked this up or why as I don't own a 9MM. I know it is at least 20 years old and still looks fine. Manufactured in Germany. Does anyone know what this is worth?
Thought I might try and trade it for something I could use.

If its just the standard 123FMJ stuff, it's just shooting fodder. Nothing collectable about it.

GECO used to offer a special hollowpoint round with a plastic capped hollowpoint called the "BAT" (Blitz Action Trauma) round. There is some interest in these, but plain old ball ammo is for blasting.

I remember GECO ball 9mm back in the 1980s. It seemed to be loaded hotter than the standard American ball of that era, if flash and blast are any indication.

I have a stash of the older Geco ball ammo and it is excellent stuff
and is indeed hotter than typical American ammo. I bought a case of
1000 rds of more recent Geco a while back and it is loaded down to
wimpy American specs, well under 1100 fps in my Browning HP.

I have some Geco about 10yrs old. It will take a magnet. Copper Coated Steel Core.
Law enforcement Grade loaded to CIP not SAMMI.

SAFE SHOOTING ALWAYS

MR835 IS GONE

(sigh) It is NOT steel core. The bullet is gilding metal clad steel jacketed and lead cored.

Great stuff, Wish I'd bought a truck load back in the 90s when it could be had for $4.50ish a box wholesale.

I believe that the maker is Gustav Genschow and Co. Geco is one of the best known German brands.

GECO is no more, being bought by RUAG of Switzerland. GECO ammo was top shelf.

I purchased 600 rds of GECO 9mm FMJ 124 gr recently. It does not pass the "magnet test" that some ranges use to disqualify ammo. At the same time I ordered 200 rds of .357 FMJ 158 gr and it did pass.

That'll be the gilding metal clad steel jacket the magnet is detecting.

Many range operators either mistakenly or ignorantly believe that any 9mm bullet that attracts a magnet believes that it must be a steel cored bullet. They don't realize that NO 9mm ammo would be allowed to be manufactured here in the U.S. nor allowed to be imported and sold on the wholesale/retail market if it had a steel or hardened metal core bullet. BATFE would make damn sure of that.

Might be of interest, I just received 200 rds of GECO 9x18 makarov that did pass the magnet test. Gilding metal clad steel jacketed bullet seems to be only used in the 9mm Luger.