Yep, I'm tracking on how a suppressor works. I'm suggesting to you that it's stabilizing your barrel harmonics. It's probably also mitigating the propensity for your muzzle to flip due to the added weight at the furthest point of the rifle.A suppressor is nothing more than a muzzle brake inside a can. It slows down, redirects, and cools escaping gasses. A 7 lbs rifle is still pretty light but it changes the recoil to something similar to my 7 lbs 8 oz 6mm Creedmoor.
Good luck!