National 9x19 AP from 1980s


#1

This thread began on https://forum.cartridgecollectors.org/t/9-mm-luger-maxxtech-interesting-steel-case/27450 but for clarity I am starting this thread with a different subject. on the original thread Galgenberg posted the sectioned National AP round below. It is the first example I have seen showing the construction of this round.

image

I am curious about the reason for the base construction on this load. It looks to me like some parts of the base wound deform into the voids on firing. Any insights would be appreciated!

I have six National AP bullets in my collection. The four loads came from boxes and were production items. The other two bullets came from the factory in 1989 and apparently were never produced or sold commercially.

Any thoughts or insights into any of them would be appreciated. If someone had other variations of the National AP loads in 9x19, please post them.

Cheers,
Lew


#2

Could the base have something to do with core/jacket separation or for stability within the barrel?


#3

Maybe will the copper/brass base act as driving belt? Prevent excaping gasses beside the projectile. And, I suppose barrels don’t like a steel projectiles
Grtz
Jaco


#4

As a machinist I think the tit on the bottom of the steel core is just a tab left there as the piece is cut off the end of the bar stock in a lathe.
Zac


#5

Zac, That was my initial impression. Then I looked at the complex shape of the inside of the brass jacket and wondered.

One possibility is that the brass jacked was drilled from rod and the conical hole at the bottom is a residue of the drill. The nipple then may be necessary to make sure the core seats properly in the jacket. Just one of a lot of possibilities.

Cheers,
Lew


#6

In my opinion the center base of the brass sabot will rupture around the steel stud due to the hollow spaces at the base being compressed by the propellant gases acting on the sabot.
This looks intentional to me. The resulting hole in the bottom of the sabot could result in the core being pressed out of the sabot by the propellant gases. But I see no way that this could happen in any consistent fashion from shot to shot. Everything from the sabot being stuck in the barrel to the sabot not separating from the core at all cold be the result.


#7

Wait, are these saboted or do they just have a base jacket? Is it intended for the base to separate?


#8

JPeelen, I agree with you that the nipple would penetrate the thin point of the base of the brass jacket. But this would only expose a small area of the steel core and the pressure per unit of surface should be roughly the same across the base of the bullet, the majority of the force pushing the bullet along the barrel would be applied to the base of the brass jacket which would then press against the base of the core. I don’t see any way for the core to be pushed out of the jacket given the difference in the area under pressure.

Strelok, I have never heard of these rounds referred to as saboted. Further this jacket is pretty thick and there are no visable slits allowing it to seperate.

Thanks for the input.

Lew