Crooked Rails on SHS Blue pistons. Who else has seen them and what vintage of piston?

[MaciekA]

I've only heard about crooked rails on SHS pistons... until now. I've finally run into the problem myself.

My datapoint:

The piston in question is the SHS blue, non-lightened, with a full metal rack. This particular piston is BEFORE the batch with the darkened steel racks, it has a light steel rack.

I think it might be time to switch to those nicer Lonex pistons.. though I wish Lonex would produce a piston with a full metal rack

Side note to other gearbox monkeys: If you're building guns with MOSFETs, loads of power, strong springs and neo motors, this problem can actually be a bit tricky to notice until you're already at the chrono phase, when you're scratching your head wondering why you're getting 280fps instead of 400.

I would always recommend checking the free movement of the piston in the cylinder before threadlocking your piston head, and before putting in the spring or spring guide -- or even sector gear. Always make sure to verify the piston you're using is able to freely drop in both directions, while tilting the gearbox at the ceiling and floor.

The other piston I've seen completely bind in a V2 gearbox is the blue PSEM piston, which is just too fat and bloated to move...