Just for fun:

What do these two items have in common that makes them unique?
 

Other than the obvious 1943 date

Copper casing??

Copper casing??

nope

Made in 1943?

Made in 1943?

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Other than the obvious 1943 date

In 1943 that round cost one cent. Lol

ooo.. that's a good one.

Neither of them are in production anymore?

Solid copper

In 1943 that round cost one cent. Lol

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That is good. But not the answer I was looking for.
Actually I don't know how much 45 ammo cost in 1943.

No correct answers yet....

I think I recall reading years ago that during WWII, maybe mid to late 1942 large amounts of copper were needed to make ammunition and casings to support the war and in an effort to conserve our copper, they looked at alternative metals for the penny. I think that is why they may have minting the zinc steel penny for a couple of years.

Just for fun:

What do these two items have in common that makes them unique?
 

Other than the obvious 1943 date

Just a SWAG:  Neither have any copper in them?

The only year both the penny and ammo were solid copper and not just plated/jacketed?

Both of these are old as Old fart...or was that your birth date?

Both of these are old as Old fart...or was that your birth date?

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Fortunately, I am not as old as the ammo or the penny.

If this were the hot and cold game, some of the previous answers are very "hot".

1943 copper penny is a mistake print. Worth big dollars. That year copper was replaced with zinc coated steel. Copper was used in the production of casings. What you have is a result of the shortage. Steel penny and steel casing

^^^^ That sounds so authoritative that I'd buy it even if it wasn't true.

Looking more at the ammo, how about this. Ammo makers (whoever those initials on casings stand for) started producing steel cased ammo vice brass cased and they used "zinc" in their production and during the same time period, "zinc" coated pennies were being minted. The reason for both of these changes was due to the war effort, specifically a copper shortage, which make both the 1943 copper penny and 1943 brass coated ammo rare.

Looking more at the ammo, how about this. Ammo makers (whoever those initials on casings stand for) started producing steel cased ammo vice brass cased and they used "zinc" in their production and during the same time period, "zinc" coated pennies were being minted. The reason for both of these changes was due to the war effort, specifically a copper shortage, which make both the 1943 copper penny and 1943 brass coated ammo rare.

I agree that both were steel. The steel penny is much rarer that the steel cased 45 ACP round. However zinc is a metal used to make brass and also used in the process of galvanizing to prevent corosion of the steel.

1943 copper penny is a mistake print. Worth big dollars. That year copper was replaced with zinc coated steel. Copper was used in the production of casings. What you have is a result of the shortage. Steel penny and steel casing

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congratulations!

We have a winner. They are both made of steel with something like a galvanized coating to prevent rust.

You can grab them with a magnet!