Mystery Round?

Hello everyone, I’m new to this website, but I wanted to get some help in figuring out a little mystery, yesterday, Sunday, Feb 3rd, 2019, me and a group of my friends went and hiked out to an old abandoned Canadian Radar base, I have been there several times before and I know the layout of the base quite well and I have never found any ammunition before, usually just empty cans of spray paint and used fireworks, but in my recent hike to the base I went to the top floor and found an unused round, as seen in the images attached to this post, I took the bullet and put it into my backpack, and brought it home, upon checking the numbers on the headstamp and doing a bit of research, I found that the first number (539 as seen in the attached image) I was lead to a Russian company called Tula Cartridge works, But upon looking at the website I could not find any rounds that are even remotely similar to the one I found, this one being comprised entirely of copper from the casing to the projectile itself, where as all the rounds they sell are not made of only copper (which I will leave a link to here, http://tulammo.ru/en/)
and as well as not matching any rounds they have on the website, I also found that the second number of the headstamp, (as seen in the attached image) is a 73, which when I tried to find any images or information corresponding to that number, came up with nothing, I tried several different search engines and websites, but the only information I could find was that it is possibly the year the round was produced, I have looked over the entire round several times to see if I could possibly find any more engravings or markings but I couldn’t find anything else, the only other defining feature on the round is a red band around the primer and where the casing and projectile connect, this has me completely stumped as to what caliber it is and whether it is from a rifle or a different firearm, so I wanted to ask everyone on here for a second opinion and to possibly find some answers about the history of the round. If anyone has any information they could share with me it would be greatly appreciated.

This is a 7,62x39 round, used in a vast amount of rifles, carbines, and machine guns.

The “73” means the year of manufacture, 1973!
As you are in Canada, this is most likely a round used by a civilian, bought in large bulk boxes sold as surplus, used in an SKS rifle. These are very popular for “plinking” :)

This is a military round, the Tulammo site is their front for civilian-marketed ammunition (which typically has the cartridge designation in the headstamp markings). Military rounds usually have only a factory name or number, a year number (or letter code for the same), and also often a lot number (the number of a production run so that it can be traced).

The 7,62x39 cartridge is a Russian cartridge developed in the 1940s as a smaller option to the full-power rifle cartridge 7,62x54R after it was found the full power rifle rounds (such as 7,62x54R, .30-06, 7,9x57 IS, and so on) had more recoil, muzzle flash, and longer range than necessary for the ranges at which combat took place - mostly less than 300 meters.

Hope this gave you some info.
Ole

As a small comment:
your round has a steel casing, which is plated in copper.
The rounds on the civilian Tulammo site are also steel - but these are coated with a polymer coat.

The idea behind both coatings is the same - less friction, less wear, less “stickyness”, and much more corrosion resistance than an untreated steel case would.

The bullet jackets are steel, washed in copper.

Ole

Ole, to keep it straight, the jackets and cases are copper clad.
No washing there.

You are totally right, I’m translating the Norwegian term for electroplated bullets (like H&N sporting bullets…), my bad.

Ole

The Russian system of Steelcase manufacture ( referred to as “bimetal”) is achieved by rolling under high pressure, a sheet of mild ( low carbon) steel between two layers of Copper, which bonds it to the steel. This is then punched, cupped, and drawn into a finished case. Where the copper is missing (extractor groove, mouth, primer pocket,) the raw steel is covered by lacquers or sealant.
CZECH steel cases, on the other hand, are Bonderised steel ( a phosphate process) and completely dipped in lacquer prior to loading ( personal view, 1993, at S&B,
Vlasim, Czech Republic).

Doc AV