Tuning need help with Beeman HW70

Hello spydie,
My last post needed some editing, but I didnt know how?
I'm sending a parts diagram with the numbers so that we can ID the parts we're talking about.
Yes the springs # CS558, conect to the two holes in the frame, and the other ends go in the one hole in the SR140. To orient the springs, (frontwards or backwards) look for wear marks from the original springs.
The trigger spring is a coil type, under the trigger adjustment screw.
BTW In one of my earlier pictures I sent this morning, I had the CS558 springs installed backwards.
The HW70 is an accurate little pistol. I shoot mine a lot. There is really no way to know how many rounds have been through this gun. I'm currently plinking at empty pill bottles, hanging from strings, at eighty feet.
They give a nice report, and action, and you don't have to set them back up.
👍

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I've got it all assembled except for the trick to get the rear cap and spring back together (it flew apart much more easily? LOL). What is the trick for that most difficult part of the assembly?
 
You'll have to build a tool
I've got it all assembled except for the trick to get the rear cap and spring back together (it flew apart much more easily? LOL). What is the trick for that most difficult part of the assembly?
I made a video, but was unable to add commentary. It shows the wooden device I made to hold the gun. And the tool I used to compress the mainspring, as well as the tool that I made to screw the receiver cap in. Give it a watch, and let me know if it helps. I used a swing hanger, a 1/2" drive socket, solid copper wires, to catch the receiver caps grooves, and tape.

 
You'll have to build a tool

I made a video, but was unable to add commentary. It shows the wooden device I made to hold the gun. And the tool I used to compress the mainspring, as well as the tool that I made to screw the receiver cap in. Give it a watch, and let me know if it helps. I used a swing hanger, a 1/2" drive socket, solid copper wires, to catch the receiver caps grooves, and tape.

Just got back from a very short 3 day vacation and watched your video, over and over and over. I think I have it figured out what you are doing. That wire that you are taping to the socket is going to be bent to fit into the the grooves of the rear cap, right? All together it looks like a great idea even if I might have missed something, but I think I know what you are doing without the commentary. If I understood it correctly, as you screw the it together, it is constantly turning the cap as the spring compresses so when it gets to the rear of the gun, it continues to screw the cap into the receiver. did I perceive your method correctly?