The Sandridge Force Five (F5) Tiny Tornado kit was likely introduced around 2000-2001 and was the later version of the Sandridge Autococker kit. These were made by (I believe) Triple A paintball after they took over Sandridge’s production.
I purchased this example from ebay in likely 2006 or 2007. I did shoot it at the time and it did function. I had planned on selling it but luckily ended up keeping it.
Since this is the Force Five model it does not use the bottomline grip block and instead has an WDP frame milled for the Sandridge board. The frame is from an Angel (LED I think?) and Sandridge (or the later company Triple A Paintball I think) mill these to accept the correct internals. The body is likely a Spanky or FBM body.
Year wise the Sandridge kits fall between the PMS Autocockers and the Eblade and were first made by Sandridge and then continued by Triple A Paintball (I think that is the correct name).
Find a write up on Sandridge Autococker history and troubleshooting at http://customcockers.com/forum/showthread.php?7749-Product-Sandrige-F-5-Information
And more Sandridge Autococker videos at: