Thanks for the feedback.
Yes, Pink Higgins had a unique style of firing his rifle.
When he cocked the rifle he used his right 4 fingers and chambered a round, a normal person would then remove the 4 fingers from the ring and use the index finger to pull the trigger. This took 1 or 2 seconds longer to fire the weapon.
What Pink did was use the 4 fingers to chamber the round and as he seated the ring he used his thumb on his right hand to fire. This was much faster and this was the basis for the TV series, the Rifeman.
I am still seeking information on the killing in Scurry Co., TX by Jeff Hardin and witnessed by Pink Higgins.