I know this is a old thread but I have a MOD 6590 that I have never fired. I purchased it many years ago and put it in a safe and forgot about it. It has a serial number that starts with RSR and four numbers the first number being a 2. Gun is stainless steel and the black plastic grip wraps around the back of the handle. The model number and serial number are laser etched.

I though I should go to the range and fire it but can not find the manual and didn't want to fire it since I don't know how to strip it down for cleaning without the manual.

Anyone have any suggestions on where to get a manual? I can not find anything on this gun on the S&W site. From what I have read on this site it appears that there were very few of these made but I find it surprising that there is nothing on the S&W site.