geez ... you must be buying barrels by the pallet . some of those rounds you might be able to work up a couple loads , then the barrel would be cooked .....
that said , awhile back I was looking at a 284 win reamer and was thinking that a guy might be able to sink the reamer in and make a chamber fairly similar in size to the 7mm stw , a guy would just have to machine out the belt portion of the chamber later .
a guy might be able to do a full length 375 h&h case necked down to .23 , with the .23x284 neck and shoulder measurements .
Actually Burnt I'm making the barrels.............What are you trying to build. a 23 STW 35 deg imp? Could do that too.........Don't let people tell you a barrel is burnt out in 500 rounds, it just ain't so. I've gotten more than 10,000 rounds each out of 2 different 243s before they totally quit shooting.
Doug.......got lots of full length H&H based cases thanks.