First do the math on virgin 270wsm cases (just for comparison)
100 Norma 270wsm @ $2 each = $200
100 Nosler 270wsm @ $2.60 each = $260
OR!! Buy loaded ammo and pull bullet to harvest brass, 5 boxes of 20 loaded ammo from either Federal or WW 7WSM @ $30 to $32.50 a box of 20 = $150 to 162.50 + Approx $20 shipping + max of $28.50 Haz Mat = total to the door of approx $210 or about $2.10 a piece on WW 7WSM brass ready to load when harvested or sligthly less with Federal Ammo for donor brass.
Selway has 14 boxes WW factory Ammo in stock right now i.e.
http://www.selwayarmory.com/winches...-magnum-wsm-150-gr-power-point-box-of-20.html
I have preferred the Federal Brass in the 7WSM so I just buy Federal factory ammo (cause can usually find it at $30 a box all else being bout same cost).
Pull bullets with Hornady collet puller (if you break puller handle buy the upgrade handle, ask me how I know this) and deprime to have virgin brass. (Of course in todays market no telling who is "making" brass for either, may come from same supplier).
Re neck size only for first firing, chamfer factory crimp slightly (it will pull back to straight opening crimp when you pull bullet), set shoulder bump "RIGHT" when chambering gets tight (2-3 firings) with Redding Competition shell holder set.
Anneal every 2-3 firings and get enough loadings out of them (at least 10-12). The performance level out of a carry weight 24" barrel gun in 7WSM is high enough to justify IMO. Not a lot of work to pull bullets and deprime brass.
I shoot the 140 Accubond at a solid 3,300fps with 69.5 grain RL23 and Fed 215 primer (super accurate and temperature stable). So I kept mine!
Or the 160AB at 3,150 with RL 26 at I believe 70 - 71 grains.
Also shot the heck of the 168 LRAB with RL 26 in the 3,075 - 3,100 range too.
I am sure you know all of the steps but put them here in case n e body has thought this out. But cost of brass is NO different to just buy ammo and harvest brass for the WSM's.
I gave up on buying brass a long time ago for 7WSM and if you want to load for the 7WSM to upper performance there is a way. Yes there is brass available, you just can't have any! LOL