I purchased a New Glock 30 SF and took it home, field stripped it and cleaned it as normal with Rem Oil. Took it to the range and shot Winchestor 230 Grain White box ball ammo and Remington UMC 230 Grain ball ammo. Every second or third shot it jams while trying to feed the ammo. The fired round is ejected fine. I took it back home and recleaned it and check for burrs or anything sticking and it seems to be fine. Once again back on the range it fails to feed on the second or third round fired. The store owner or manager were not present thus no gunsmith to look at it. The lady running the range said bring it back when they are here because she had never seen a Glock jam. I admit, this is my 8th Glock and only one I have ever had jam. Any help is appreciated.