I have a used 7MM Weatherby mag in a Mark 5 action that will not hold any kind of a group less than about 3". It was made in Japan in Jan. 1994, 26" SS #2 contour. I seat a 175gr Speer GS just into a new case which gives me a total COAL of 3.781. I place in chamber and close the bolt, after removal the total COAL is 3.767. Which leaves only 14 thousands of bullet in case when the bullet hits rifling. That gives me a free bore of about .402. The Speer GS has a lot of bearing surface, any other bullet will leave the case before it hits the rifling, really not good! Am I missing something important here or is the throat gone? What is good free bore on replacement barrel?
I got this weapon for long range Mule Deer and Elk so I want the extra velocity. Now, long range for me is about 500 yds. my eyes and reflex isn't what they were many years ago.
Thanks for any information on this post.
AIRBORNE