Info on FN 7.9mm Mauser armor piercing appreciated

Hello fellow collectors, I’m Tim, ECRA member and cartridge collector especially of armor piercing cartridges from Germany. New to the forum but a long time reader.
I searched for old topics regarding the FN 7.9mm AP cartridge but didn’t find what would answer my question.
Per my understanding pre WW2 / WW2 FN 7.9 AP are quite similar in design to the german SmK bullet regarding ogive, material and construction, cannelure. It is as far as I know steel jacketed with a full length steel core.
Sadly I have no samples on hand but seen pictures of postwar 1950s 7.9 Mauser FN AP cartridges (presumably Egyptian contract) which seem to star a different bullet. Judging from pictures, those newer bullets have a bit ‘fatter’ ogive and the cannelure is rolled in a way resembling the double cannelure of the 7.62 NATO FN P80 AP bullet.
Surely FN will color and crimp bullets to whatever the customer specifies, but I am curious if they changed the jacket to gilding metal or brass after the war and if FN might have changed overall construction of 7.9 AP bullets akin to the P80 bullet with a shorter penetrator, no lead sleeave and lead base. Bullet measurements / weights / drawings / cross sections would be appreciated.

I have pictures of the cartridge on hand but refused to post them in the first place since I was concerned about copyright issues.

Yours, Tim

Tim, what actually is your question?

Here a cutaway image from Kevin Gross:

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Thanks for the input. I am asking wether bullet construction / material changed form the pre war sample you posted to the sample pictured below since FN came up with a new bullet construction in 7.62 NATO and may have just scaled that up to 7.9mm.
Credits for the picture to Jim Miles (

I guess only FN will know that and those who actually knew are not with FN anymore or are not even alife anymore.

According to the German D 50/8a of 1941, a green tip, case mouth and primer annulus was used to identify the armour piercing versions of the Belgian Army 7.65 mm as well as the FN 7.9 mm cartridges.

As far as can be seen on the very tiny, blurred image, the 7.9 mm hard core was boattailed as in the sectioned FN cartridge (Kevin Gross) above. This is different from the cylindrical base of the German core. Other differences are the bullet weight (11.8 g, not 11.55 g) and the cupronickel (not steel) jacket.

Edit: Sorry, I misunderstood your question. Limited my response to the differences between prewar FN 7.9 mm armour piercing and German SmK.