I believe you can get a GP100 357 and send it to clark custom for a 10mm conversion.  Pricey, but very nice.

Thanks Pablo... Couple more questions...  Where in the heck do you find 10mm barrels with gas holes for DI?  All i can find are back preasure barrels. 

Also, for any reason would a 6.8spc side charging handle upper and bcg NOT work?  Just thinking about ideas and generating knowledge. 

Thanks!

Can someone help me understand what is done to a BCG to allow for a 40/10mm case to be used.  Specifically the bolt face on a DI bolt.