300 win mag Throating dimensions

[Cojaq]

Hello Fellow LRH's. I am wondering a few things about throating dimensions and free bore. I currently shoot a 300 win mag. I am stepping up to the 215gr VLD's and quite possibly 230gr VLD's. So as some of you know the MV is not all that great from a 26" bbl. I would like to increase MV by at least 200fps. I have been reading a lot about bbl length and free bore. I was wondering if something similar to the 338+P can be accomplished as far as the chamber/lead dimensions are concerned. If there are any Smiths out there that may have some working knowledge and ability to do this. I have tried a few different seating depths and what not, but no real positive difference. Of course I have considered a longer bbl and will be switching to a 30" tube soon. But it seems that only minimal fps gains will be reached with the increased bbl length. My goal is to reach something like 3000 fps or maybe a little higher with out having pressure issues. This isn't so much as a hunting rig as it is an ultra long range ringer. I realize I should consider a bigger cartridge, but I have what I have and really don't want to pay another 4000 for a paper puncher at this time. Maybe later. So....to all the smiths and persons that can speak from experience....any suggestions to this quest?