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Author Topic: M90 piston o-ring upgrade?  (Read 161 times)

RedRyder

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Re: M90 piston o-ring upgrade?
« on: October 29, 2020, 02:15:01 pm »
You might not find a difference between a teflon or properly fitted rubber o-ring.
The correct o-ring size is 22 x 1 mm. It should fit a bit the ring groove should be a hair bigger than the 1 mm o-ring thickness.

This way when it fires, the pressurized gases push the o-ring down and get behind it in the groove and force it out to firmly seal at the cylinder wall.
When it is free wheeling the o-ring retracts a bit and has near zero friction in this state.

After your experiment, please let us know if teflon can do any better than that.

Most of all...... have fun...!!!

Gil