When my Rem Model 7's (two each - 223 Rem) had factory barrels on them I tried the Limbsaver rubber damping device on both. Both rifles had the barrels free floated in factory stocks. One rifle had the factory plastic stock, the other a wooden stock. The action was bedded on the plastic stock.
They grouped about 1" or so consistently at 100 yards if my memory serves me right without the damping device. Before free floating, groups were very inconsistent from a cold barrel 5 shot strings. All groups shot with tailored reloads and quality bullets, i.e. Sierra and or Nosler. My standard for a varmint rifle is 1/2 or so MOA so I wasn't satisfied.
The device did reduce the groups on one of the Model 7, SS 20" barrel, about 3/8 to 1/2" so. In addition to the size, the group clustered more uniformly both vertically and horizonility. I had to play around with the location of the device on the barrel but it did work. There was no affect on the 18" barrel Model 7 in the wooded stock. Yes it destroys the look of the rifle for a traditionalist like me but I'm all about performance so I'd rub cow manure on the barrel if it produced significant performance improvement.
Yet I though I could do better so I made a significant investment in both rifles as explained below.
Both these rifles now group in the 1/2 moa range consistently. I had the barrels replaced with Douglas Match barrels, 20" in length and one contour heavier than the factory barrels. I also replaced the factory plastic stock and wooded stock with B&C Metalists stocks. These rifles have performed extremely well in the field, as a light weight stalking (walking around) varmint rifles. Case in point, in 2019, I had a 98% success rate in the field with the SS Model 7. This year I'm 6 for 6 on ghogs. All shots under 250 yards.
The Model 7 CS actually shoots better but I developed extreme clean barrel flyers. This I believe it due to over cleaning with a new solvent brand but I'm working that issue this summer.
I sold the Limbsaver device.