ID of two US 40x53SR TP projectiles


On a Canadian museum website I have found two images of US made 40x53SR (so called “HV”) projectiles.
The caps that are usually crimped on top are not fitted.
As we see the shape of the projectile bodies (solid) is quite unusual.
Is there any information or explanations and diagrams available?

40x53SR_TP_cap missing_unknown_USA40x53SR_TP_cap missing_unknown_USA-


Alex, the one on the right is the Practice w/spotting charge XM428E1.




Fede, the spotting charge is located around that centre pin then?
Is it energetic material or those Calyume light emitters in glass ampules?



Fede, as usual you have it all! Thanks again!

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