22LR in either CCI Velocitors or Aguila Supermax are ballistic-wise, very close to 22 mag. I carry a .45, 2 different 9mm's, or a Ruger SR22 , depending on time of year and clothing. I feel very safe with 10 Velocitors in my SR22. No recoil, fast reaquiring of target, and like the OP, I can make a quarter size group of 10 in your forehead in about 5 secs. . I am 53 years old and have been shooting since I was 8. I dont recommend 22lr to a beginner, but if you are dedicated and practice regularly, a .22lr will do the job. The Massad ( Israeli Secret Service) used the 22Lr as standard carry for over 2 decades, and they took out a fair number of targets in that time.