Piston/Activator Rail Breaking Glitch

I was making a restone piston clock in the End, and I wanted to make a thing that could blow up on chance.
I put an activator rail in front of the pistopn head. Then I put a light Weighted Pressure Plate on block in front of the Rail, and one block down. I put an Activator Rail next to the Plate, and I activated the clock. Then, both Activator rails broke! I think it's wierd, but it's just a small bug