Not true... Kimber says not to use it as a regular diet. Proofing and concealed carry with it is OK according to Kimber. Here's a quote from Kimber: "+P ammo manufactured to SAAMI specs is fine to use as a defensive round or for occasional range use only. Our pistols are rated to handle +P ammo. However, we do not recommend a steady diet of them, as they are rough on the pistol and will accelerate the wear on the gun and may shorten the life of the recoil spring. "Kimber manual says not to use +P ammo.
Well they do say too much of anything is bad for youKimber says it's OK to run +P rounds just as long as it's not a steady diet.
"NOTE Although this Kimber firearm is capable of functioning with +P ammunition in the appropriate caliber for the firearm, a steady diet of +P ammunition may affect the wear characteristics, shorten the life and endurance of your firearm, and necessitate more frequent maintenance and replacement of parts. Do not use +P+ ammunition."
1000RR was last seen in Oct 2021 so I doubt you'll be receiving an answer from him.Kimber manual says not to use +P ammo.