Anyone want to take a stab at this... Bullet maybe??

[jraven]

Looks like a bullet, but has a funny pattern....

 

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[Monty]

Same thing only swagged bullet. The crosshatch is swaged on and then it is lubricated with a waxy lube with a white powdery surface. I think you can still buy them from Hornady? Monty

 

[l.cutler]

It looks like a Buffalo Bullet, a modern conical bullet made for muzzleloaders. I have used .58 caliber ones and they are identical to yours. They are made in several different calibers. Also the rifling on yours looks like muzzleloader rifling, it is much deeper than cartridge firearm rifling.

 

[dkw]

http://forum.treasurenet.com/index.php/topic,93945.0.html

 

[jraven]

http://forum.treasurenet.com/index.php/topic,93945.0.html

Thanks for the ID guys, Yep looks like a perfect match...