Can the power plant be designed to be fully charged with just one or two pump strokes?
Yes. This is pretty easy to accomplish and results in a gun that is highly efficient. For example, my second gun was modified for this operating point. Two pump strokes resulted in consistent power outputs exceeding 13.5 ft-lbs. In comparison, a newer Benjamin .22 caliber air rifle exhibits about 12 ft-lbs with 10 pump strokes. I have tremendous respect for Benjamin air rifles, having had one for over 40 years. I hope my own guns will be able to hold up as well as the classic Benjamin. Still, the gun’s primary purpose at this point is as a hunting air rifle. As such, the new power plant is best applied toward achieving the highest power output within a reasonable amount of effort expended. This appears to be around the 31-38 ft-lb category.