While it is a very good round and one I would use rather than the 7mm Rem mag due to the better brass available ,most folks do see a big enough improvement over the 7mm rem mag and none ballisticaly over the 7mmSTW , yet you have to neck down and fire fore cases , to the vast majority of people that seems like way more work that its worth.
I probably would not do the Ackley improvement on the 300 win mag as their is not going to be that big of an increase in capacity and since its already an oversized case the velocity gain will be slight. The main real benifit to Ackley-izng this case is to cut back on case streching. Depending on your reamer you may or maynot have to turn the necks , the only way to tell is make up a dummy round and check it against the reamer.
I'm sure that either RCBS or Redding makes regualr dies for this round and if not any of the neck bushing dies for the 300 win mag or win mag improved will work for the 7mm neck size if the correct bushing are used.
I highly doubt that Shilen will touch anybodys barrel than theirs other than to remove it. Best bet would be to ask around , some smiths will splti up the cost of buying a reamer if you let them keep it.
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