Dear Paul and forum members,
I have noticed that the small locking screw for the main pivot bolt in my FWB 124 has started turning a bit. I noticed after making a small reference mark, and after a shooting session it had turned back out just a bit, less than 1/4 turn. I don't think it moved for the 1000+ shots or so. I gently turned it 1/4 until it stopped, slightly past my reference mark. The rifle barrel would hold its own weight at this point when cocked and I proceeded to test fire it for zero, and the groups had opened up quote a bit, almost 1" @ 20, instead of a pea size group. I then loosened the screw back just a little, back toward my reference mark and it started shooting tight again. I was surprised that the accuracy would change so much, since the screw was neither tightened or loosened more than 1/4 turn. As the screw loosened past may reference mark, just slightly, the poi on my scope changes vertically by 1/2" as well, this happens with a movement no more than 1/8 turn. Since the rifles tune by Paul, it has been a true pleasure to shoot and I am very thankful he took my rifle In when he did, so this is not a complaint, just an observation. The main pivot bolt has never moved since the work was done, and I am wondering if it would be advisable to just maintain the position of the screw as I shoot session to session, or to use something like vibratite on a small part of the thread to keep it in its sweet spot?
Thanks for your time,