case for bullet

[jefg231]

why do these lok different?

 

[Charlie P. (NY)]

If they have grooves (often with red paint in them) they are dummies for test cycling the action and checking feed. If the nose is curled in they are likely blanks.

Dummies

Blanks

 

[Monty]

I fouind a bunch of those cases with grooves in the sides and looked them up one time. There was a particular machine gun that was prone to sticking cases in the chamber when over heated and the grooves prevented it. Sorry I can't remember which one. Also, some had grooved chambers for the same reason as well as the blanks you cited for testing cycling. I couldn't see the two examples in question they were so small on my screen, but probably either blanks or grenade launching ammo. I think it is solved. Monty

 

[Charlie P. (NY)]

I think the Tokarev rifle used a fluted chamber that collapsed the case slightly to make extraction easier (they initially ripped the rims off the cases when dirty). H&K use a similar fluting with their blow-back system. Usually it's around the neck as well as the sides. Guess it's a possibility.

 

[Monty]

I believe it was the HK with the fluted chamber I am thinking about. I tried to reload some of the cases from the 7.62 Nato round and right away found out it wouldn't work. I trashed nearly a thousand cases that was given to me because of it. That was when I was still green behind the ears...............well more so than now! M nty

 

[jefg231]

thanks

 

[Gunny71]

Yep, HK G3 and the spanish CETME have grooved chambers.