The regular Taurus M85 is
comparable to the S&W J-frame size gun. This is not to say that they are the same. Let's put it this way, the Mod 85 uses the same speedloaders as the J frame Smith. Taurus calls this their compact or small frame.
The Mod 669 Taurus (six shot .357) uses the same speedloader size as the Smith K and L frame. Taurus calls this their medium frame.
Now Taurus has their .44 Mag and .454Casull chambered revolvers. I don't know if they are the same frame size as each other or not. Who knows what they call those things!
Now, to totally confuse things, I have a Dan Wesson .357. DW calls
this their small frame, and yet it uses the same speedloaders as the K and L frame Smiths, but the frame is substantially larger than even the L frame. DW's large frame revolvers (their .357 Maximum, .41Mag, and up are freaking
huge!!
Colts are another matter also.
So I guess I really didn't answer your question, but I hope this helps some!