Needle Bearings On The End of the Spring?

[Born Again]

How would a ptfe washer sandwiched between two steel washers fare?

You'd be better with two PTFE washers between two steel washers. The coefficient of friction of PTFE on PTFE is similar to ice on ice.

[Dornfelderliebe]

You'd be better with two PTFE washers between two steel washers. The coefficient of friction of PTFE on PTFE is similar to ice on ice.

Thanks. I shall now try to find some on my favourite auction site. I'm sure that the ptfe will be protected by the steel.

[NickG]

PTFE deforms and migrated , so you will probably see velocity varying , delrin is probably better.
Your piston rotates in the tx anyhow, just make sure your piston weight/ top hat isn't stuck and grease it .

[Dornfelderliebe]

I have noticed, admittedly in my budget guns that the rotation has been pushed back (layman's terms) to the rear of the spring guide vs the end block.
I saw this most visibly in my Paratrooper even though it's spring guide allows rotation there is a shiney circle worn into the rear block corresponding to a similar circle of the rear of the spring guide.

It just goes to show how important a good spring bearing set up is.