On the AR15/ M16, the spring is retained by the buffer. The buffer is retained by a pin located at the lower outer edge of the extension tube.
using a buffer retainer
The bolt carrier would not return, another round would be chambered, and you'd likely have to replace a bolt carrier, buffer tube, buttstock (if using a fixed buttstock), and buffer spring (if the spring was in the extension tube). You could also cause injury to yourself if the bolt carrier ended up going through the back of the extension tube.
Stock
No. A standard AR15 has a buffer tube that runs inside the stock that contains the recoil spring.
Yes it is complete, no it does not include a buffer or spring- and is rather pricey IMHO.
when the extension of the spring increases the weight hung on it also increases
The relationship is Hooke's Law: the extension of a spring is directly proportional to the force applied.
The amount the spring is stretched is called the displacement.
multiply the force with length.
The amount the spring is stretched is called the displacement.
The rate or spring constant of a spring is the change in the force it exerts, divided by An extension or compression spring has units of force divided by distance, law which states that the force a spring exerts is proportional to its extension.
The Extension :)