K, L, N; sized from smallest to largest.
N frame 357 Magnum
It is a K frame. The original .357 Magnum was an N frame (Model 27). The K frame is smaller and lighter.
The model 65 is built on the K frame.
It uses the "K" frame. The Model 66 was the Model 19 in stainless, and with a target trigger. But it was only made in .357 Magnum; it was never made in .44 Magnum. That was the Model 29.
K frame.
Model 27. Made in the 73/74 time frame. Call S&W and they can tell you when it shipped from the factory.
L frame, blue steel revolver in 357 Magnum
Yes, a model 66 is a K frame revolver.
The 357 magnum model 27 was produced in 1935 and ceased in 1994 That serial number dates to late 1953 early 1954 time frame.
100-500 USD
L frame, .357 magnum, full length lug, 6 shot
The Model 19 is a 357 Magnum