Neck tension? I can not measure neck tension, I can measure bullet hold, I fired 4 boxs Federal GM 300 Win Mag in a non Weatherby rifle in a non Weatherby chamber, after 4 boxes and a lot of adjusting the 74 th round when through the absolute canter, in two hours another shooter put the next five rounds in the same hole, I applied the leaver policy to that rifle, I lefter the way I founder. And, I will tell you the chamber in that rifle is no common ordinary chamber. Most of the adjustments involved scope base, rings and scope.
The next rifle, a Winchester model 70 300 Win Mag was sent back to Winchester, after 6 boxes and reloads the rifle shot patters, not groups, if I enjoyed wasting my time at the range shooting a 300 Win mag I would take the Winchester to the range to determine if Winchester made improvements before sending it back. It has been 4 years, and I will never understand how honing, polishing and reaming will reduce the diameter and length of a chamber, the ugliest chamber I have ever seen, I purchased the ugliest rifle ever built for $120.00, I purchased it for parts, but first I took it to the range with 5 boxes of reloads, different cases, bullets, powder and primers, no patterns, just small groups, again, I applied the leaver policy.