6 mm USN

My cartridge of 6mm USN have a nickel plated primer, on municion.org, all the others cartridges showed have a brass plated primers. The crimp around the ball looks good. So is normal or it is a reloaded case?

What type of bullet is it loaded with?

normal bullet, here the pictures

Have you weighed it? It’s possible you have a rare early 135gr cartridge, as opposed to the more common 112gr loading.

I will have to weigh my 112gr cartridge to see. If your cartridge is 1.5g/23gr heavier, it may well be the 135.

Just weighed my example. It clocked in at 19.8 gm/305 gn. So if your cartridge weighs approx 21.3 gm/328 gn, you might have an early 135gr load.

Thank you, for informations, I’m not able to weight it for the moment, have to find a precision weighter. I just remark that there is something impressed on the ball, it looks like a “w”. My first guess is for winchester, but why on a case made by UMC?

My first impression of your cartridge was that the bullet looked as tho it had a copper jacket with tin plating, but my perception of web pictures isn’t to be relied on. The W does indicate manufacture by Winchester, and Winchester did use tinned copper jackets. Such bullets are uncommon (or nonexistent?) in UMC cartridges. The round is almost certainly a reload. Jack

Yes, the bullet had a tin plating copper jacket. So the cartridge seem to be reloaded, my question is if it is a government’s arsenal or a personnal reload? (The ball crimp is identical to a 30-06 headstamped F A 4 17)

Laurent: The 6 m/m Lee had a rather brief service life in the U.S. Navy, and I think nickeled primers weren’t available until after the Lee was withdrawn from service before 1910. It’s likely a loading by a private individual. Jack

I didn’t guess reload because of the FMJ bullet. That is much less common among U.S. civilian cartridges, though I suppose it’s not impossible.

Actually, Full Metal Patch bullets were quite common in US sporting calibers that were popular “back in the day”, in calibers such as 6mm USN, 30-30, 30 Army, and so on…


Well, there you go.

I know they’re still popular in Europe. I suspect their “good sense” retention is better than ours (at least with regards to civilian firearms preferences).

I have a cartridge like Laurent’s except no “W” on the bullet and it has a separate copper tip. It comes in at 303gn.

Laurent–Your cartridge is a reload. U.M.C. would never have used a Winchester bullet in a factory load. Also, the first nickel plated primers in the U.S. were introduced by Remington Arms Co. in 1923. So your cartridge is a reload using a Winchester bullet made after 1923. Any factory loaded 6mm Navy with a nickeled primer would have the REM-UMC headstamp, not U.M.C. which was discontinued in 1910 with the merger of U.M.C. and Remington.