No powertube spacers?

[Hobbez]

In my recent post about fixing the wifes mag, I was advised to change the powertube spacers in a lvl 7 bolt. It didnt really makes sense to me at first, as that valve doesnt have PT spacers, just a spring. I bought my first mag in '88 and never really took part in the x-valve or ULE movement, so this didnt seem abnormal to me. Can anyone give me a bit of info about this? Why was the spring replaced? Is it worth buying PT spacers and converting it or just let it go until I'm ready to install the lvl10?

[XM15]

If you got bolt stick it ment the spring was bad and needed to be replaced. The springs would go bad fairly often. When they switched to the spacers it was rare to get bolt stick.

[Coralis]

Basically the spacers adjust the position of the power tube oring when the marker is gassed up (the pressure forces the oring forward or up the tube and spacers limit the travel then the oring seals on the bolt stem). As your sear and bolt lip wear down over time that sealing point changes so over time you would need a smaller spacer. The springs were supposed to self adjusting however they tended to wear out faster than the sear or the bolt lip and would cause problems (even though this was pretty rare as well.)