What do I have here?

[Jacks Grampa]

Came with a box of other reloading tools from a garage sale.

 

[Melvin]

Looks like expander die for a neck turner kit, maybe 25 caliber
My Sinclair neck turner uses something similar.

 

[hoz53]

Came with a box of other reloading tools from a garage sale.

yeah thats an expanding mandral

 

[RustyInBend]

Expander Mandrel ... yup. You can use calipers to tell you the size if it's not discernable from the markings.

 

[20 TAC]

PMA??

 

[mgunderson]

Might be a Sinclair.

 

[Rick300]

PMA??

Sure looks like the PMA I have

 

[divingin]

Might be a Sinclair.

Sinclair has a drop-in mandrel and solid-capped top on the die, doesn't it?

 

[WSnyder]

Sinclair has a drop-in mandrel and solid-capped top on the die, doesn't it?

2nd gen does, 1st gen is similar looking to the one shown. The one shown doesn’t look to be a Sinclair. As stated above most likely a PMA with those mandrel markings and the shape of the expander mandrel. Their stainless expanders have that shape.

 

[Jacks Grampa]

Thanks folks. It did come in a box with some other PMA tools.

 

[JMayo]

Yep one it a turning mandrel, flat on one side of bottom
The other is a mandrel for the press that goes with that die.