7.62 mm cartridges assembled with .30 api bullets


The following link is for a PDF on the 1975 evaluation of loading 7.62 x 51mm cartridges with .30 caliber API and incendiary bullets for use in the USAF 7.62mm minigun: dtic.mil/cgi-bin/GetTRDoc?AD … tTRDoc.pdf




The report is dated 1975 but the actual tests occured in 1969. Most of the surviving cartridges are Incendiaries headstamped LC (+) 69.

There are also some cartridges with later headstamps with what appear to be incendiary bullets that may be fakes.




Thanks for your input, the picture and correction on the year. A 1969 test date makes more sense since that puts it right in the middle of the Vietnam war and the minigun was in use on the AC-47 Spooky gunships. To many dates shown in these reports!

I wonder if the .30 caliber API and incendiary bullets used were stand alone old stock or recovered from the breakdown of .30-06 ammunition stores?

Any idea as to whether the loaded 7.62 x 51mm rounds were all placed in belts or 20 round boxes or some of both?



Since the purpose was to test the rounds for functioning, I assume they were fed in the conventional manner, whatever that was.

The bullets were pulled from existing stocks of Cal .30 cartridges. Some of the Incendiaries show bullet puller signs. There did exist, at the time, two API bullets designed specifically for the 7.62mm NATO case and it would seem that those bullets would be used, but, the report did say the bullets were pulled from Cal .30 so I assume they were. I don’t have one of the API cartridges. If I did, I would pull the bullet to see for myself.



I have been told that there is something not quite right about the bearing surface of a .30cal API bullet (when pulled from a cal. 30 case and then loaded into a 7.62x51) in terms of firearms functioning / accuracy or propellant capacity issues. Does anyone know what that is about? I had also heard that something about the non boat-tail vs boat-tail bullets made a distinct difference in the .308 vs 30-06 projectile swapping.


I seem to remember an Olive drab color tip that was for use in Mini guns also. Or has this been debunked?



I wouldn’t read too much into those tests. I think they were more of a “keep busy” project or “use up the money before it lapses”.

Two good things that came out of it were the cartridges for collectors to look for and add to their collection.




Here are the only two I have, next to an API.

Left to right h/s’s
LC 74 (+)
TW 69 (+)
F A 51 API



Check the two with a magnet. They should show the typical Incendiary attraction. Also, the '74 date seems way too late. Do they show any of the crimping cannelure?

Your API appears to be a T101E2, although it could be a T101E1. Hard to tell from that angle.




74 seemed to be a really late date to me also. Both bullets magnetic, but not at the tip. I cant see any visible crimping cannelure on either one.



You’d probably have to pull a bullet (partially at least) to see if the smooth cannelure is there. Otherwise, ??