I had one that was doing that on just one chamber. A trip back to Ruger and it was good to go. They replaced the cylinder and did a little fitting here and there.
Blackfoot
If warming the engine a bit before driving would damage it there would be cautions in the manual. Of course none of us read the manual, we know how to work a car.
Blackfoot
YES, I use them and am working on my last 5K of #1 1/2 (spp) Have never had an issue of any kind; As far as running through the press and seating they are he best I have ever used. Shooting, never a problem.
Blackfoot