Hold the rifle vertical and place the fingers of one hand on either side of the barrel at the end of the foreend so that the fingers are also just touching the foreend. A light grip is important. Then with the other hand undo the front action screw. You shouldn’t feel the barrel move, if you feel the barrel move the bedding needs redoing.
The other could be you need to jam the projectiles into the lands. I use to shoot 168 vld Berger’s in my 7mm mag and I jammed them about 15 thou into the lands. I used about 72.5gr 2217 and federal magnum primers.
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