1. Not sure what swivels you got, but the one on mine just pulled straight out and pushed in. The sling I put on it had better swivels so I switched to those.
2. I bought the T3 for my 10 year old son to use. He is shooting Remington Managed Recoil rounds through his rifle. They are 125 grain bullets. During a practice session he put 3 rounds within a 1" square at 100 yrds. I'm not worried about accuracy with those rounds in that gun.