I called Ruger and was told they stopped the internal lock a few years ago on the LCR, SP101, and GP100. My next revolver will be a Ruger. I have all Smith revolvers, but my 442 Pro and 640 Pro are the last of the Smiths without the lock that I will buy. My next will be a GP100 or SP101 as I will not buy any gun with an internal lock.