Nice gearbox inside this Arcturus, radiused, reinforced and QD spring. I had to cut more than a coil from my M100 spring, heat up the end, straighten them smooth it out.
Cycling between 1.14-15-16J now.
RPS sucks though, 12, thinking maybe change the motor or put in some 16:1 gears, apparently it comes with 18:1 inside. Stock motor couldn't pull back and M130 spring I tried in it, just choked.