Loaned out my trusty old 34 to a neighbor and it came back with a very rough cocking effort and erratic shot string. When I cocked it I was like holy poop. I think the spring is broken, going to make a spring compressor and have a look. I chronographed it last year at 660 with Crosman 14.3s for just under 12 ft. lbs. Looking to bump it up if possible. Vortek has a kit with spring guide etc for about a hundred bucks. They claim to increase to 720 fps or so but with a higher cocking effort. One fellow on another forum claimed a weaker spring from Macarri, unknown to me, will gain the same increase with reduced cocking effort. Counter intuitive but possible? Anybody have experience with this.