Unfamiliar indention on ammo

[TheDan]

So what is this for?

 

[shortround]

Looks to me like Wolf, Russian manufactured, steel-cased ammo.

Since it is steel and Berdan primed, I would hazard a guess the indentation is designed to support the case head for a high-pressure round, or it might be a way the Russkies make ammo for some kind of linked system.

How did you do the "circular" insert? That is good work.

 

[TheDan]

Yeah, I was thinking that maybe its a groove for some type of stripper clip, but I don't know that the Russians use that might be chambered in 30.06
I used photoshop...

 

[Taurus]

I think it's what they call a belted round.

 

[TexMex247]

I'm guessing it was made for some kind of belt-fed gun.

 

[M. Sage]

No, that's not belted. And I don't see where it would have a use for belt-fed, even if anybody used .30-06 these days...

Probably used for something in the manufacturing process, but I'd like to get my hands on a piece of fired brass.

 

[txgunner00]

Not belted. Belted is 7mm mag, 300 win mag, etc.

Engineered weak point maybe? Something to do with steel's expansion/ contraction rate being different from brass? That's where a case head separation would typically occur.

 

[M. Sage]

I've been thinking about this a bit... I'd bet it's to allow some expansion to PREVENT a failure. It'll let the cartridge expand so the shoulder goes tight against the chamber and the base pushes tight against the bolt face.

 

[Wolfwood]

I've been thinking about this a bit... I'd bet it's to allow some expansion to PREVENT a failure. It'll let the cartridge expand so the shoulder goes tight against the chamber and the base pushes tight against the bolt face.

my money is on this answer

 

[Mikewood]

Not belted. Belted is 7mm mag, 300 win mag, etc.

Engineered weak point maybe? Something to do with steel's expansion/ contraction rate being different from brass? That's where a case head separation would typically occur.

That sounds right to me.

 

[txgunner00]

I've been thinking about this a bit... I'd bet it's to allow some expansion to PREVENT a failure. It'll let the cartridge expand so the shoulder goes tight against the chamber and the base pushes tight against the bolt face.

This is what I was getting at. Weak point as in an expansion/ contraction area, not a failure point.

 

[robocop10mm]

.30-06 was not designed for steel cased ammo. They probably found a need to modify the design of the case to allow it to work in rifles intended for brass cases. The case not only is the container for the primer, powder and bullet, it is a gasket to prevent hot, high pressure gasses from leaking into your face. Steel does not expand/contract like brass. The groove likely allows the case to seal properly.

 

[TheDan]

I'd like to get my hands on a piece of fired brass.

PM me your address and I'll send you one. Might be a week or two before I get a chance to shoot them, tho.

 

[Deavis]

Expansion in that area of the case is going to be minimal, if you are thinking that it would "pop" to seal, I don't think so. I could be wrong and a fired casing would prove it, but I'm betting there is a different motive there. It may very well be to reduce the amount of material actually in contact with the chamber, and thereby reduce the force needed to remove a round in an auto-loader. In other words, if it doesn't contract as much (why steel needs lube) they you can also remove the area that bears against the chamber and achieve a similar effect. Similar to reducing muzzle pressure indirectly via banding a bullet, lower friction.