50 CAL SHELL?

[PowerDetecting]

I have had this for about 10 years now I just now ran across it again it was given to me from a friend of my mom's who was in Vietnam. I was wondering if anyone could possibly tell me more about it? this is what is reads on the shell

around the shell reads

28113791-001F
30 MM TP PGU-15/B
H JA87F012-022


Bottom of the shell reads

28107310-Y
USE87C017-038

 

[PowerDetecting]

Now thinking 30 mm since it says 30mm on part of the stamping on it

 

[PowerDetecting]

I think I found out about it with some research it seems to be a TP target Practice shell
PGU-15/B - Target Practice (TP): A ballistically matched, low cost TP cartridge for use in training, weapons
testing, and aircraft systems checkout

 

[Aarong81]

Thats nowhere close to a .50 cal in size. Heres a comparision to a few different shells, .50 BMG is shown on the bottom row and your 30mm is bottom row far right.

 

[Ant]

Measure the opening using the metric scale.

 

[Aarong81]

Thats nowhere close to a .50 cal in size. Heres a comparision to a few different shells, .50 BMG is shown on the bottom row and your 30mm is bottom row far right.

I completely forgot to attach the picture........