Main Spring Optimum Compression

[Ronno6]

i know it is on here....somewhere.....but.....

What percentage of maximum compression should a mainspring see in practice?
Seems to me that it about 90% of available travel, but  don't know how I come by that number.........

[mikeyb]

i know it is on here....somewhere.....but.....

What percentage of maximum compression should a mainspring see in practice?
Seems to me that it about 90% of available travel, but  don't know how I come by that number.........

Most springers i work on need about 4mm overtravel on the piston to get trigger latch. Spring can be coil bound  AFTER that but not before. If power stroke piston travel is 100mm then IMO optimum spring compression would be 96% with piston latched for that rifle. These springs can handle being near coil bound for every shot.