Most of my shooting is at an indoor range. I've used it when the storage temperatures have been down in the 50's (parked outdoors) with no problems. One shooter in a club I belonged to used straight STP. parked outside when it was in the 30's and couldn't operate the slide. I don't know what the temperatures are where you are at so I would suggest mixing up a half ounce or so, apply some, and if your domestic situation allows, store the gun in the refrigerator overnight. If it is still a little too stiff dilute the half ounce down with more ATF and try it again. If it still doesn't work use straight ATF or the thin oil recipe. Let us know what your experiences are.