Hi The cocking bolt/hammer spring mech.

I just got into these, the above is an example of the use of an SSG "spring stop guide" system yes ??
how does it take apart?
is the larger spring suposed to "fill" the gap it occupies? mine is 2mm short ?
the inner small spring over the rod ? WHY, what for??

The only idea is that the outer spring is to short to allow the "half cock" to operate without load ??
Confused
Help
Not like the modern 1377 !!