I have had very bad luck with Remington UMC and "green box" 9mm ammo. Numerous failures of all kinds in otherwise reliable handguns, such as a G17, M9 and 226. The only decent Remington handgun ammo is Golden Sabre, which is excellent....stay away from anything else. I witnessed a Glock 17C KB with 9mm UMC yellow box. Try Winchester white box, which is consistant, safe and accurate. Some weapons have feed ramps which are ammo sensitive. Part of getting a new handgun is testing to see which loads work and which dont. For example, my Beretta 92 doesn't work reliably with Corbon 115 and 125 grn +P ammo. The blunt Sierra bullet has a tendency to nose dive in OEM Beretta magazines....every handgun has ideosyncracies you just have to figure them out. In any event, with the exception of Golden Sabre, Remington 9mm ammo is garbage and is potentially dangerous, especially yellowbox UMC.