I just bought a brand new G19 gen 3 and love it! After firing about 100 rounds through it i went home and started to clean. While I was cleaning the lower frame I noticed behind the 2 rails there seemed to be some excess plastic so i took a small screwdriver and cleared it out. Is there suppose to be a gap behind those rails? The are no cracks and the rails feel solid. The only thing I can think of is that there was excess plastic from factory. I have not fired it since i saw this...Thanx!!