5.56, USA556JF 50g frangible? Taken apart, pic heavy.

[Shadow9mm]

So I got this round with a batch of once fired military brass. It has been wet tumbled and I suspected ruined so I decided to pull it apart and see what was inside. The tip looks gray but I could see copper under it so I suspected I had just messed up a painted tip and that it might be a tracer. I was a touch shocked when I pulled the the bullet and found this monster. Best guess is some sort of lead free or frangible? looks similar to USA556JF and Z556NX1 from pics, which are 50g frangible.

link to USA557JF looks pretty similar.
https://palmettostatearmory.com/winchester-5-56-40gr-jacketed-frangible-ammunition-20rds-box-usa556jf.html

head stamp WMA 18
Bullet weight 50.4g
powder unknown, weight 25.3g

 

[Shadow9mm]

Here are the other pics. Powder was clumpy. Center is the pulled bullet, heep in mind, it only weighed in at 50.4g. Left is a standard 55g fmj. Right is a 75g match

 

[Unclenick]

Have you put a magnet to it?

 

[Shadow9mm]

Have you put a magnet to it?

Just did. its non magnetic.