Twist Rate for 300gr SMK\'s in 338/300 RUM? Have any of you built a rifle in this chambering? I plan to shoot mostly 300 Grain SMK's but may try some higher BC VLD bullets down the road. Recommended twist rate that will stabilize the longer 'custom' 300 grain VLD bullets out there without winding the 300 SMK's up too fast? Recommended chamber neck diameter using Fed. Gold cases and Rem. cases? Also which bullets would you recommend my trying out besides the SMK? Currently considering: 338/300 RUM throated for 300 SMK Tight neck (not sure what to get here....) Pac Nor 30" Supermatch barrel Holland Brake 1:10 Twist 3 Groove Thanks!