Right here
http://www.huntingnet.com/forum/blac...red-twice.html but XTP MAG should have been a clue to the caliber. Hornady does not list the .429 240gr as a XTP MAG.
The first bullet weighs about 240g, and was fired from a 45acp pistol at about 900 fps real real close.
It took longer to type this response than use the search feature.