[davepl]

Here's a picture. It pops out just after it rotates around to the relief area for the pin boss. Even that would seem impossible, and it leaves a little scratch where it exits (can't see it in the photo well enough), but it does it.

He's going to try a ring that is deeper radially that should have a harder time coming out, but its still uncomfortable not knowing, even if that "fixes" it.

Everything from back spacing on the ring to the amount of barrel in the piston checks out according to spec. Checked everything we have numbers for on the piston and then some!