anyone have any problems with runout on this chambering?im thinking about having one built but i dont the really short neck,seems like the 7x300wsm is the way to go,to get a longer neck.any and all info is apreciated-tia-dave
Don't sweat the neck length. Runout comes from your reloading dies and a longer neck won't fix that. The neck has to be long enough to positively hold the bullet during handling and the 7 mm WSM has more than enough. You gain a little case capacity using the factory round and there is none too much in any short mag.
You will be able to more easily get great reloading dies (Redding Competition Bullet Seater and type S bushing dies) in the factory round and that will help with bullet run out.
I just took delivery of my custom 7x300wsm and I am very pleased with it. don't know much about any of the short mags but I know mine shoots extremely well. it is a defiance deviant action ' benchmark medium palma 1-9 twist barrel XLR element chassis and rifle basix trigger set at 1.9 lbs topped with A nightforce atacr 5.5-25x56. the builder told me that the neck length does make a difference, look up vince b. in the UK and read his story about the 7x300 wsm and you will be impressed I think. good luck on your decision.