I was looking at one of your posts from about 9 months ago. You where mostly talking about using RL17 in a 25-06AI. You also mentioned that you shoot a 250 Ackley. Have ever played with the RL17 in your 250? If so, what where the results.
I can highly recommend the 7 Saum or the WSM. However one will need a Magnum bolt head the same as one would for the belted cases.
If you want a 7MM race horse that will do what the WSM cases can do contact McGowen barrels as they have chambering reamers for the Cooper Cartridges which are a similar design as the Gibbs line.
I am shooting a 180gr Accubond from my 17" 338 handgun barrel at 2800fps with change.