I’ve Got a ruger m77 7mm mag from early 90’s bought used. Have had same leupold vx1 for twenty years. Always been on never had any problems. I missed a buck a couple seasons ago, which was a long slitghly difficult shot. But as usual after a miss I shot at the range. The gun was off a good 6x6 inches so made a minor adjustment and shot again and it went the other way nearly the same. Then shot again without adjusting and it hits bullseye. I’ve changed ammo tightened everything from scope mounts which weren’t loose to screws on stock which were able to turn a little. Still the same situation when I shoot. I might hit true on the first shot but the second would be a flyer then third the opposite direction. I’ve maintained the gun cleaning with standard wire brush and solvent at the end of the seasons. I’m the 30 years I’ve had the gun I can’t imagine I’ve put more than 60 reds through it.