Unknown 7.62x51 - Page 14 IAA Journal Nov-Dec 2012


#1

I originally posted the photos below back in 2008, seems they got lost along with a lot of other stuff when the forum had the problem.

Browsing through the latest issue of the IAA Journal I was surprised to see a question on page 14 regarding a cartridge exhibiting the same traits as the two I have.

All I know about the spent cases is that I picked them up on a military range sometime between 1984 and 1994. If memory serves the range was somewhat disused and the spent cases were discovered while doing the mandatory police call for brass while shutting the range down. These two case were clearly different from anything I had seen before and I hung onto them asking around for an explanation of the holes in the cartridge case shoulder. I never got a satisfactory answer.

What were these thing fired in, are the holes fired formed or were they in the case before firing?

Someone out there knows the answer, thanks.

HWBX


#2

Hi HWBX, these were fired in a 90 mm M67 recoiless rifle fitted with the 7.62 mm M49A1 subcaliber training device.

According to its manual: “The device utilizes a case blow-out principle through six equally spaced holes in the chamber shoulder section of the barrel. These holes permit the cartridge case to be blown out, and limit the pressure which in turn lowers the velocity to match ballistically the major caliber round” (sic).


#3

I came across a Nato 7.62 x 51 empty brass case that is head stamped LC 68 and it only has 4 evenly spaced holes on its shoulder. Anyone have any ideas? Thanks, joe


#4

hwbx,

If you search the IAA Journal index, which you will find under “Membership & Journal”, there are several references to this round: 488/14, 489/47, 490/44. The first reference is to the issue 488 where you found the original question and the others are the answers which, by the way, includes the information the Fede has just kindly provided.

I do recommend that people check the index which is searchable.