I didnt think the blue was Inc. because I thought it would have a black tip with blue, or is that API? How about the yellow?
Is the Austrian 9mm tracer old, or about 20 years..?
Is the .60 API?
The blue tip is incendiary. Black and blue tip code is API, but only used by Israel. Never heard of frangible .50 BMG...
The yellow tip is most likely just paint used to mark the target socks the gunners fired at. When the bullet passed through the target sock, it left traces of paint. Different gunners used different colors, so you could tell who hit the target. This was done "in the field" and not at the factory. The belts were dipped tip first into a shallow tray of paint then left to dry. The sloppy appearance of the yellow paint suggests a non-factory application. My grandfather flew on B-17s during WWII and verified this information.
Can't help you with the links.
The .45 case is in fact steel.
I'd say the 9mm tracer is 1980's vintage or later.
Your .60 cal has a tinned projectile. There were so many experimentals and variations of the .60 cal. it boggles the mind. Could be a ball round, high pressure, inert dummy, ???.
Post your pics and questions on the forum at www.cartridgecollectors.org and you will get excellent information and answers to all your questions.
The .50 cal rounds look like they have been those links since WWII. I wonder of they were someone's souvenirs from the war...
Yellow tip .50 is associated with Dominican Republic AP. I just recently transacted 500 rounds of such. I would suspect that these are those pulls that were inserted into that brass. The tip off to me is the outstanding quality of the yellow paint that was spoken of re: the 'finger-painted' elegance of the paint application. If not, I think that ca. 1940 there was a yellow tip spotter round. If I get a chance today I will verify that.
With US military ammunition, the color of the primer seal has NO bearing on the load type. Red primer seal DOES NOT mean incendiary or anything else. just a color so it was easy for QC personnel to see. The yellow tip on your cartridge is too thick and sloppy to be a factory applied marking. It is also not a reload using a Dominican AP projectile, again because of the appearance of the tip color as well as the general appearance of the cartridge. I still think this is a target marking cartridge as I mentioned in my earlier post. There were no Observation loads during WWII that fit this description. The "T" series numbers are too high to be a 1943 product. Post these pics on the IAA website for the .50 cal collectors to comment on. As for the pink tipped round, this does not match the description of the chrome-moly core test rounds in my reference material. These were pink over black tipped.
As I stated earlier, I just handled 500 rounds of Dominican yellow tip. More than a few of them had that little black tip on the yellow tip. And they were quite similar in the paint marking quality. I have no idea how long these have been in the information requestors possession. They can be projectile transfers, although I tend to doubt it. If they are pulls, I don't see collet marks. As I stated, the information which I wrote comes from the publication I identified.
Excellent. Please let us know what you find out. Pay special attention to the light blue tipped round. As I could not tell which primer ring went with which tip, I did not comment on it directly. That might be the most interesting one.
I have included a similar link at the bottom of this to the last one I posted. It is for the second volumn of the DIA Spotters guide. I don't know if you will have use or not, but at least you are now able to find it. I downloaded it and printed several copies a while back and it comes in handy at gun shows to know whats in "the box".