All ejector L.C. Smiths have two ways of holding the for-end on, one is the "J" spring found on all L.C. Smiths and the other is the roller release found on ejector guns and non ejector guns after around 1919 (except Field grades).
The "J" spring makes contact in the front of the barrel loop while the roller release makes contact in a notch at the back of the loop securing it in. The roller release uses a coil spring and the "J" spring uses a short armed tension spring to hold it up.
If the spring for the roller release was broken, the release would move very easily, and if the "J" springs spring was broken, the "J" spring would stay down inside the recess.
You stated that it snaps on, but can be pulled off, so that sounds like the coil spring for the roller release is broken.
